Uce Physics Practical Experiments 51283r

535/3 UCE PHYSICS PRACTICAL EXPERIMENTS Table of Contents 1. Experiment to determine the acceleration due to gravity. ......................................................... 2 2. Experiment to determine the width of a paper. ........................................................................... 3 3. Experiment to determine the acceleration due to gravity. ......................................................... 4 4. Experiment to determine the acceleration due to gravity. ......................................................... 5 5. Experiment to determine the relative density of a liquid........................................................... 6 6. Experiment to determine the acceleration due to gravity. ......................................................... 7 7. Experiment to determine the relative density of the material of a solid. ................................ 8 8. Experiment to determine the density of rubber. ........................................................................ 9 9. Experiment to determine the density of paraffin and mass of a boiling tube. ..................... 10 10. Experiment to determine the mass of a metre rule. .................................................................. 11 11. Experiment to determine the mass of a metre rule. .................................................................. 12 12. Experiment to investigate the relationship between the depression of a loaded metre rule and the distance between its s. ................................................................... 13 13. Experiment to determine the focal length of a concave mirror. ............................................. 14 14. Experiment to determine the focal length of a concave mirror. ............................................. 15 15. Experiment to determine the refractive index of a glass block............................................... 16 16. Experiment to determine the refractive index of the material of a glass block. ................... 17 17. Experiment to determine the refractive index of glass. ........................................................... 18 18. Experiment to determine the refractive index of glass. ........................................................... 19 19. Experiment to determine the refractive index of a glass block............................................... 20 20. Experiment to determine the refractive index of the material of a glass block. ................... 21 21. Experiment to determine the focal length of a converging lens. ............................................ 22 22. Experiment to determine the focal length of a converging lens. ............................................ 23 23. Experiment to determine the focal length of a converging lens ............................................. 24 24. Experiment to determine the focal length of a converging lens. ............................................ 25 25. Experiment to determine the focal length of a concave mirror. ............................................. 26 26. Experiment to determine the constant of a resistor. ................................................................. 27 27. Experiment to determine the resistivity of a bare wire. ........................................................... 28 28. Experiment to determine the resistance of the filament of a torch bulb. ............................... 29 29. Experiment to determine the internal resistance of a dry cell. ................................................ 30 30. Experiment to determine the constant of a bare wire. .............................................................. 31 31. Experiment to determine the internal resistance of cells. ........................................................ 32 32. Experiment to determine the resistivity of the material of a wire. ......................................... 33 33. Experiment to determine the diameter of a bare wire. ............................................................. 34 34. Experiment to determine the resistivity of a wire..................................................................... 35

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535/3 UCE Physics Practical Experiments.

1. Experiment to determine the acceleration due to gravity. In this experiment, you will determine the acceleration due to gravity. (a) Suspend the pendulum bob from a retort stand such that it is 0.10m from the floor. (b) Adjust the length of the pendulum to 1.20m.

(c) Displace the bob through a small angle θ as shown in the figure above. Release it to oscillate in a vertical plane. (d) Determine the time for 20 oscillations. (e) Find the time, T, for one oscillation. (f) Raise the pendulum bob (by reducing the length of the pendulum) by a distance h = 0.10, 0.20, 0.30, 0.40, 0.50 and 0.60 m and in each case repeat procedures (c) to (e). (g) Record your results in a suitable including values of T2. (h) Plot a graph of h (along the vertical axis) against T2 (along the horizontal axis). (i) Find the slope, s, of the graph. (j) Calculate the acceleration due to gravity, g, from the expression:

.

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535/3 UCE Physics Practical Experiments. 2. Experiment to determine the width of a paper. In this experiment, you will determine the width, w, of the graph paper provided.

(a) Tie the pendulum bob on one end of the string. (b) Tie a knot on the string such that the length, w, from the centre of the bob is equal to the width of the graph paper provided. (c) Suspend the pendulum bob from a retort stand. (d) Adjust the length, l, so that it is equal to 0.100m. (e) Displace the bob through a small angle and release it to oscillate in a vertical plane. (f) Determine the time, t, for 20 oscillations. (g) Find time, T, for one oscillation. (h) Repeat the procedure from (d) to (g) for values of l = 0.200, 0.300, 0.400, 0.500 and 0.600m. (i) Record your results in a suitable table including values of T 2. (j) Plot a graph of T 2 (along the vertical axis) against, l (along the horizontal axis). (k) Find the slope, S, of the graph. (l) Read and record the intercept, C, on the T 2 - axis. (m) Calculate the width, w, of the graph paper provided from the expression: C = Sw. DISMANTLE THE SET UP 3

535/3 UCE Physics Practical Experiments. 3. Experiment to determine the acceleration due to gravity. In this experiment, you will determine the acceleration due to gravity g.

(a)

Tie the piece of thread provided to a pendulum bob.

(b) (c)

Measure up a length, l of 140cm of the pendulum. Suspend the pendulum bob from a retort stand using a length of 140cm of the thread as shown in figure 1. Displace the pendulum through a small angle and release it. Record the time, t, for 20 oscillations. Repeat procedures (b) to (e) for l = 120, 100, 80, 60, and 40cm. Record your results in a suitable table, including values of T, log10T and log10 l, where T is the period of oscillation. Plot a graph of log10T against log10 l. Find the slope, S, of the graph. Calculate the acceleration due to gravity, g from:

(d) (e) (f) (g) (h) (i) (j)

g = 4S.

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535/3 UCE Physics Practical Experiments. 4. Experiment to determine the acceleration due to gravity. In this experiment you will determine the acceleration due to gravity, g.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l)

Clamp the given spring provided and a metre rule as drawn in figure 1. Read and record the position of the pointer on the metre rule. Place a mass m equal to 0.100 kg on the scale pan and record the new position of the pointer on the metre rule. Find the extension of the sping, x, in metres. Remove the metre rule. Pull the scale pan downwards through a small distance and release it. Measure and record the time for 20 oscillations. Find the time, T, for one oscillation. Repeat the procedures (f ) and (g) for values of m equal to 0.200, 0.300, 0,400 and 0.500 kg. Record your results in a suitable table including values of T 2. Plot a graph of T 2 (along the vertical axis) against m (along the horizontal axis). Find the slope, s, of the graph. Calculate g from: g=

.

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535/3 UCE Physics Practical Experiments. 5. Experiment to determine the relative density of a liquid. In this experiment you will determine the relative density of liquid, L, provided.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m)

Clamp the metre rule vertically. Suspend the spring with a pointer beside the metre rule. Suspend the beaker from the spring using knitting thread, as shown in the figure above. Record the initial position, P, of the pointer on the metre rule. Pour 50 cm3 of water into the beaker and record the new position of the pointer. Find the extension, y, produced. Repeat procedures (e) and (f), for 100, 150, 200 and 250 cm3 of water. Remove the beaker, empty and dry it. Repeat procedures (c) to (g), using liquid, L. Call the extensions produced, x. Record your results in a suitable table. Plot a graph of y (along vertical axis) against x (along horizontal axis). Determine the slope, S, of the graph. Calculate relative density from the expression: Relative density = .

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535/3 UCE Physics Practical Experiments. 6. Experiment to determine the acceleration due to gravity. (a) Clamp the spring provided and a metre rule as shown below.

(b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m)

Read and record the position of the pointer on the metre rule. Suspend a mass m = 0.2kg from the spring. Record the new position of the pointer. Find the extension of the spring, x, in metres. Pull the mass vertically downwards through a small distance and release it to oscillate. Determine the time for 20 oscillations. Find the time, T, for one oscillation. Repeat the procedures (c) to (h) for values of m = 0.3, 0.4, 0.5, 0.6 and 0.7 kg. Tabulate your results including values of T2. Plot a graph of T2 against x. Find the slope, S, of the graph. Calculate the acceleration due to gravity, g, from the expression: S=

.

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535/3 UCE Physics Practical Experiments. 7. Experiment to determine the relative density of the material of a solid. In this experiment, you will determine the relative density, ρ, of the material of solid X provided.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m) (n)

Record the mass, M, of the solid, X provided. Suspend a metre rule from a clamp using a piece of thread. Adjust the metre rule until it balances horizontally. Read and record the distance of the balance point, P, of the rule from end A. Suspend the solid, X at a distance d = 10 cm from end A of the metre rule. Immerse solid X completely in water in the mug. Suspend a 100g mass from a point, Q, between P and B. Adjust the position of Q until the metre rule balances horizontally, with X completely immersed and not touching the mug as shown in the figure above. Measure and record distances z, and y. Repeat procedure (e) to (i) for values of d = 15, 20, 25, 30 and 35 cm. Enter your results in a suitable table. Plot a graph of z against y. Find the slope, S, of the graph. Calculate the relative density, ρ, of the material from the expression: ρ =

.

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535/3 UCE Physics Practical Experiments. 8. Experiment to determine the density of rubber. In this experiment, you will determine the density, ρ, of the rubber provided. (a)

Record the mass, M, of the metre rule provided.

(b)

Suspend the rubber bung, W, at a distance d = 5 cm from the zero end of the metre rule. Balance the metre rule with its graduated face upwards on the knife edge as shown in figure 1. Measure and record the distances, d1 and d2, of the knife edge from the zero and 100cm marks of the metre rule respectively. Repeat procedures, (b) to (d), for values of d equal to 10, 15, 20, 25 and 30 cm. Tabulate your results, including values of (d2 – d1) against (d1 – d). Find the slope, S , of your graph. Determine the density , ρ, of rubber from the expression:

(c) (d) (e) (f) (g) (h)

ρ = 0.5 S.

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535/3 UCE Physics Practical Experiments. 9. Experiment to determine the density of paraffin and mass of a boiling tube. In this experiment, you will determine the density, ρ, of paraffin and mass, M, of the boiling tube provided. (a) (b) (c) (d) (e) (f) (g) (h)

(i) (j) (k) (l) (m) (n)

Pour water into a 250 ml measuring cylinder to about one third of its capacity. Read and record the volume, Vo of water in the measuring cylinder. Tie a piece of thread round the neck of the boiling tube leaving the two ends of the thread free to enable you lower the tube or pull it out of the measuring cylinder. Carefully lower the empty boiling tube into the water in the measuring cylinder and leave to float. Read and record the new water level, V in the measuring cylinder. Measure volume Vp = 10 cm3 of paraffin. Using the free ends of threads, partially pull out the boiling tube and pour the paraffin into it. Lower the boiling tube and content into the measuring cylinder as shown in the figure below.

Read and record the new water level, V. Repeat the procedure from (f) to (i) for total volume of paraffin Vp = 15, 20, 25, 30 and 35 cm3. Record your results in a suitable table including values of Vw = V – Vo. Plot a graph of Vw (along the vertical axis) against Vp (along the horizontal axis). Determine the slope, ρ, of the graph. Find the intercept, M, on the Vw – axis. DISMANTLE THE SET UP

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535/3 UCE Physics Practical Experiments. 10. Experiment to determine the mass of a metre rule. In this experiment you will determine the mass of a metre rule. (a) (b) (c)

Balance the metre rule provided on a knife edge with the graduated side facing upwards. Note the balance point P and record its distance from end B. Place a mass m of 10 g on top of the metre rule at the 10 cm mark and balance the arrangement as shown in the figure below.

(d) (e)

Read and record the distances l1 and l2. Repeat the procedures (c) and (d) for values of m = 20, 30, 40, 50 and 60 g.

(f)

Record your results in a suitable table including the values of (l2 – l0) and

(g)

Plot a graph of m (along the vertical axis) against

(h)

axis). Find the slope of your graph.

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. (along the horizontal

.

535/3 UCE Physics Practical Experiments. 11. Experiment to determine the mass of a metre rule. In this experiment, you will determine the mass of the metre rule provided.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k)

Place the block of wood on the table so that it rests on its smallest cross-sectional area. Place the knife edge on top of the block. Balance the metre rule provided on the knife edge with its calibrated face upwards. Record the position C at which the metre rule balances. Suspend a 100 g mass at the 2 cm mark and adjust the rule until it balances again. Determine the distances l1 and l2 of C and of the weight respectively from the knife edge. Repeat procedures (e) and (f), with 6, 10, 14, 18, and 22 cm marks respectively. Record your results in a suitable table. Plot a graph of l1 against l2. Find the slope, S, of the graph. Calculate the mass, M of the metre rule, from the expression: M = 100S

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535/3 UCE Physics Practical Experiments. 12. Experiment to investigate the relationship between the depression of a loaded metre rule and the distance between its s. In this experiment, you will investigate the relationship between the depression od a loaded metre rule and the distance between the s. (a) (b) (c)

Attach a pointer at the 50cm mark of the metre rule provided. Place the metre rule so that it lies horizontally on the two knife edges provided. Clamp a half-metre rule scale verically and place it near the 50cm mark of the metre rule as shown in the figure below.

(d)

Adjust the knife edges such that the distance, d, between them is equal to 90 cm and they are equidistant from the 50 cm mark of the metre rule. Read and record the position of the pointer, yo, on the scale. Suspend a mass of 500g at the 50cm mark of the metre rule. Read and record the new position of the pointer, y, on the scale. Hence find the depression, x, of the metre-rule at its mid-point where x = y – yo. Remove the mass from the metre rule. Repeat procedures (d) to (h) for values of d equal to 80, 70, 60, 50 and 40 cm. Enter your results in a suitable table including values of log x and log d. Plot a graph of log x (along the vertical axis) against log d (along the horizontal axis). Find the slope, n, of the graph.

(e) (f) (g) (h) (i) (j) (k) (l)

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535/3 UCE Physics Practical Experiments. 13. Experiment to determine the focal length of a concave mirror. In this experiment you will determine the focal length f of the concave mirror provided.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m) (n)

Fix the mirror in the holder. Focus light from a window onto the screen. Measure and record the distance x between the screen and the mirror. Arrange the mirror, the mounted bulb and the screen as shown in figure 2. Adjust the object distance U = 45 cm. Close the switch. Move the screen until a sharp image of the object is formed on it. Measure and record the image distance V. Open the switch. Repeat procedures (e) to (i) for values U = 40, 35, 30, 25 and 20 cm. Enter your results in a suitable table including values of (U + V) and UV. Plot a graph of UV against (U + V). Find the slope f of the graph. Calculate the difference between f and x.

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535/3 UCE Physics Practical Experiments. 14. Experiment to determine the focal length of a concave mirror. In this experiment, you will determine the focal length of a concave mirror. (a)

Align the torch bulb, the concave mirror and the screen as shown in figure 2.

(b) (c) (d) (e) (f) (g)

Adjust the distance d to 15 cm. Close switch K. Adjust the position of the screen to obtain a sharp image of the filament of the bulb on the screen. Open switch K. Measure the distance v of the screen from the mirror. Repeat the procedures (b) to (f) for values of d = 20, 25, 30, 35 and 40 cm.

(h)

Record your results in a suitable table including values of

(i)

Plot a graph of

(j)

Find the slope, s, of the graph.

(k)

Calculate the focal length f, from the expression: f = .

.

. (along the vertical axis) against v (along the horizontal axis).

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535/3 UCE Physics Practical Experiments. 15. Experiment to determine the refractive index of a glass block. In this experiment, you will determine the refractive index of the glass block provided.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m) (n) (o) (p) (q)

Fix the plain sheet of paper on a soft board using the drawing pins provided. Place the glass block on the plain sheet of paper and trace its outline WXYZ. Remove the glass block. Mark a point, N on WX such that WN is about a quarter of WX. Draw a line ON perpendicular to WX. Draw a line SN at an angle i = 10o to ON as shown in the figure above. Fix pins P1 and P2 vertically on SN. Replace the block on its outline. Looking through the glass block from side ZY, fix pins P3 and P4 such that they appear to be in line with the images of P1 and P2. Remove the pins and the glass block. Draw a line through P3 and P4 to meet ZY at M. M to N. Measure angle θ. Repeat the procedure from (f) to (m) for values of i = 20o, 30o, 40o, 50o, and 60o. Record your results in a suitable table including values of sin i and cos θ. Plot a graph of sin i (along the vertical axis) against cos θ (along the horizontal axis). Find the slope, S, of the graph. HAND IN YOUR TRACING TOGETHER WITH YOUR ANSWER SHEETS. 16

535/3 UCE Physics Practical Experiments. 16. Experiment to determine the refractive index of the material of a glass block. In this experiment, you will determine the refractive index, n, of the material of the glass block provided.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m)

Fix the plane sheet of paper on a soft board using drawing pins. Place the glass block on the sheet of paper so that it rests on its broader face and trace its outline ABCD. Remove the glass block. At point, O, about 2 cm from A, draw a line RO at an angle θ = 80o to AB. Fix pins P1 and P2 along RO and then replace the glass block onto its outline. Looking through side DC, fix pins P3 and P4 as shown in the figure above. Remove the pins and the glass block and draw a line through P3 and P4 to meet DC at P. P to O. Measure angle β. Repeat procedures (d) to (i) for θ = 70, 60, 50, 40, and 30o. Record your results in a suitable table including values of cos θ and cos β. Plot a graph of cos θ (along vertical axis) against cos β (along horizontal axis). Find the slope, n, pf the graph.

HAND IN THE WHITE PAPER (with the traced outline ABCD) WITH THE REST OF THE WORK.

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535/3 UCE Physics Practical Experiments. 17. Experiment to determine the refractive index of glass. In this experiment, you will determine the refractive index of glass. (a) (b) (c)

Measure and record the width, w, of the grass block provided. Fix the sheet of paper provided on a soft board using drawing pins. Draw two lines PQ and RS intersecting at right angles at O as shown in the figure below.

(d) (e)

Draw a circle of radius 3.00m having O as its centre. Draw a line AO making an angle θ equal to 20o with PQ. Stick two optical pins along AO. Place the glass block with the longest edge along RS and trace out its outline. Looking through the opposite face of the block stick two other optical pins along CD so that all the four pins are in line. Remove the block and draw lines DC and CO. Replace the block in exactly the same position as before. Repeat procedures (e), (g) and (i) for θ equal to 30o, 40o, 50o, and 60o. Remove the glass block and draw perpendiculars from the points where the lines intersect the circle to line POQ. Measure and record distances x and y. Plot a graph of y (along the vertical axis) against x (along the horizontal axis). Find the slope of the graph. Attach the sheet of paper you used to the answer booklet.

(f) (g) (h) (i) (j) (k) (l) (m) (n) (o)

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535/3 UCE Physics Practical Experiments. 18. Experiment to determine the refractive index of glass. In this experiment, you will determine the refractive index, n, of glass.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m) (n) (o) (p)

Fix a white sheet of paper onto a soft board. Place the rectangular glass block in the middle of the sheet of paper. Trace the outline, ABCD, of the block. Draw a normal PR to meet AB at O such that AO is about one-third of AB. Draw a line SO at an angle I = 30o to the normal at O. Fix pins P1 and P2 to stand vertically on SO. Replace the block onto its outline. Looking through the block from side DC, fix pins P3 and P4 such that they appear to be in line with P1 and P2. Remove the block and draw a line XQ through P3 and P4 to meet DC at Q. O to Q. Produce XQ to meet PR at T as shown in figure 2. Measure OQ and QT. Repeat procedures (e) to (l) for values of i = 35o, 40o, 45o, 50o, and 55o. Enter your results in a suitable table. Plot a graph of OQ against QT. Determine the slope, n, of the graph. HAND IN THE TRACE

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535/3 UCE Physics Practical Experiments. 19. Experiment to determine the refractive index of a glass block. In this experiment, you will determine the refractive index, n, of the glass block provided. (a) (b) (c) (d) (e) (f) (g) (h)

Measure and record the width, w, of the glass block provided. Fix the plain white sheet of paper on a soft board using drawing pins. Place the glass block on the white sheet of paper so that it rests on its broad face and trace its outline ABCD. Remove the block from its outline. Draw a normal MN to cut AB and DC at R and Q, respectively, such that AR is 2.0 cm. Replace the block onto its outline. Fix a pin vertically at R. Fix a second pin vertically at E at a distance, x, = 1.5 cm from Q, as shown in the figure below.

(i)

Looking through the glass block from side DC, fix a third pin vertically at F, such that it appears to be in line with pins at R and E. (j) Remove the glass block and the pins and F to E. (k) Produce FE to meet the normal MN at G. (l) Measure angle α. (m) Repeat the procedure from (f) to (l) for values of x = 2.0, 2.5, 3.0, 3.5 and 4.0cm.

(n) Tabulate your results including values of tan α, (o)

Plot a graph of

(p) (q)

Find the slope, S, of the graph. Calculate n from the expression:

and

(along the vertical axis) against

S=

. (along the horizontal axis).

.

HAND IN YOUR TRACING TOGETHER WITH YOUR ANSWER SHEETS 20

535/3 UCE Physics Practical Experiments. 20. Experiment to determine the refractive index of the material of a glass block. In this experiment, you will determine the refractive index, n, of a material of a glass block provided.

(a) Fix the white sheet of paper on a soft board using drawing pins. (b) Place the glass block in the middle of the paper. (c) Trace the outline ABCD of the glass block. (d) Remove the glass block and draw the normal NO to AB. (e) With O as centre, draw arc ZY of a circle of radius, r = 4.0 cm extending from the line NO to AO. (f) Draw a line WO making an angle, i = 10o with NO. (g) Replace the glass block. (h) Stick two pins P1 and P2 along WO. (i) Looking through the glass block from side CD, stick two pins P3 and P4 in line with the images of pins P1 and P2. (j) Remove the glass block and the pins; and draw a line through the marks of P3 and P4 to meet CD at M. (k) O to M. (l) Measure and record angle θ. (m) Draw the line EQ normal to NO; and measure its length, x. (n) Repeat procedures (f) to (m) for values of i = 20, 30, 40, 50, and 60o. x (o) Enter your results in a suitable table including values of /4 and sin θ. x

(p) Plot a graph of /4 (along the vertical axis) against sin θ (along the horizontal axis). (q) Find the slope, n, of the graph. HAND IN YOUR TRACING PAPER.

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535/3 UCE Physics Practical Experiments. 21. Experiment to determine the focal length of a converging lens. (a) (b) (c) (d)

(e) (f) (g) (h) (i) (j) (k) (l) (m) (n)

Place the lens facing a window with the screen behind it, then adjust the position of the screen until a sharp image of a distant object is focused on it. Measure and record distance, x, between the lens and the screen. Arrange a lit bulb and the screen such that the distance, d, between them is slightly greater than 4x. Measure and record the distance, d.

Place the lens between the bulb and the screen as shown the figure above. Adjust the position of the lens to obtain a clearly focused magnified image of the bulb on the screen. Measure and record the distance y1 between the bulb and the lens. Displace the lens towards the screen so as obtain a clearly focused diminished image of the bulb on the screen. Measure and record the distance y2 between the bulb and the lens. Repeat procedures (c) to (i) for values of; d+5, d+10, d+15, d+20 and d+25 cm. Record your results in a suitable table including values of y2 – y1, (y2 – y1)2, d2 and [d2 – (y2 – y1)2]. Plot a graph of [d2 – (y2 – y1)2] (along the vertical axis) against d (along the horizontal axis). Find the slope, s, of the graph. Calculate the focal length, f, of the lens from the expression: s = 4f

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535/3 UCE Physics Practical Experiments. 22. Experiment to determine the focal length of a converging lens. In this experiment, you will determine the focal length, f, of the lens provided.

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l)

Focus the image of a distant object onto the screen provided. Measure and record the length, F, between the screen and the lens. Connect the bulb, the dry cells and switch, K, in series as shown above. Arrange the bulb, the lens and the screen as shown. Adjust distance, x, between the bulb and the lens to 1.5 F. Close switch, K. Adjust the position of the screen to obtain a clear image on it. Measure the distance, y, between the lens and screen. Repeat procedures (e) to (h) for x = 2.0 F, 3.0 F and 4.0 F. Tabulate your results including values of xy and x + y. Plot a graph of xy against x + y. Find the slope, f, of your graph.

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535/3 UCE Physics Practical Experiments. 23. Experiment to determine the focal length of a converging lens In this experiment, you will determine the focal length, f, of the lens provided. (a) Focus the image of a distant object onto the screen provided. (b) Measure and record the length, f, between the screen and the lens. (c) Connect the bulb, the dry cells and switch K, in series as shown below.

(d) (e) (f) (g) (h) (i)

Arrange the bulb, the lens and the screen as shown. Adjust distance U between the bulb and the lens equal to 60 cm. Close the switch K. Adjust the position of the screen to obtain a clear image on it. Measure the distance, V, between lens and screen. Repeat the procedures (e) to (h) by displacing the lens towards the bulb by distance x = 5, 10, 15, 20, and 25, cm.

(j) Tabulate your results including values of (U – x), (k) Plot the graph of

1

/V

(l) Find the intercepts on (m) Calculate

and

against 1

/V

1

and

/V and 1/(U – x).

/(U – x). 1 /(U – x) and record them as I1 and I2 respectively.

.

(n) Calculate the focal length from the formula: f=½

1

.

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535/3 UCE Physics Practical Experiments. 24. Experiment to determine the focal length of a converging lens. In this experiment, you will determine the focal length, f, of the converging lens L provided.

(a) (b) (c) (d) (e) (f) (g) (h)

(j)

Connect the bulb, the dry cells and the switch, K in series. Arrange the bulb, the lens and screen as shown in the figure above. Adjust the distance, u, between the wire gauze and the lens L to 70cm. Close switch K. Adjust the position of the screen to obtain a sharp image of the cross wires on it. Measure and record the distance, v, between the screen and the lens. Open the switch. Repeat procedures (c) to (g) for values of u = 60, 50, 40, 30 and 20 cm. u Enter your results in a suitable table including values of /v . u Plot a graph of /v against u.

(k) (l)

Read and record the intercept, C, on the u-axis. Find the slope, S, of the graph.

(m)

Calculate the focal length, f, of the lens from the expression, f =

(i)

25

1

/S.

535/3 UCE Physics Practical Experiments. 25. Experiment to determine the focal length of a concave mirror. In this experiment, you will determine the focal length, f, of a concave mirror.

(a) Arrange the concave mirror and the illuminated wire gauze such that their centers are at the same height above the bench and lie in a straight line as shown in Figure 2. (b) Place the mirror at a distance, u, equal to 80.0 cm from the illuminated wire gauze. (c) Place the screen between the wire gauze and the mirror such that a sharp image of the gauze is formed on the screen. The screen must be slightly displaced from the straight line between the centers of the mirror and the wire gauze. (d) Measure the distance, v, of the screen from the mirror. (e) Repeat procedures (b) to (d) for values of u = 70.0, 60.0, 40.0 and 30.0 cm. (f) Record your results in a suitable table. v

(g) Plot a graph of v (along the vertical axis) against /u (along the horizontal axis). (h) Find the slope, S, of the graph. v (i) Find the value, t, of v when /u = 0. (j) Calculate the focal length, f, of the mirror from: f =

.

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535/3 UCE Physics Practical Experiments. 26. Experiment to determine the constant of a resistor. In this experiment, you will determine a constant, k, of the resistor, Q provided.

(a) (b) (c) (d) (e)

Connect the circuit shown in the figure above. Starting with length x = 0.20 m close switch K. Read and record the voltmeter reading, V, and the ammeter reading, I. Open switch K. Repeat the procedure from (b) to (d) for the values of x = 0.300, 0.400, 0.500, 0.600 and 0.700 m.

(f) Record your values in a suitable table including values of (g) Plot a graph of

(along the vertical axis) against

.

(along the horizontal axis).

(h) Determine the slope, k, of the graph. DISMANTLE THE SETUP

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and

535/3 UCE Physics Practical Experiments. 27. Experiment to determine the resistivity of a bare wire. In this experiment, you will determine the resistivity, ρ, of the bare wire, W, provided.

(a) (b) (c) (d)

Connect the ammeter A, switch K, dry cell E and wire W, as shown in the figure above. Adjust distance, l , of the wire to 20 cm. Close switch K and record the reading, I, of the ammeter. Repeat procedures (b) and (c) for values of l equal to 30, 40, 50, 60, 70 and 80 cm.

(e)

Record your results in a suitable table including the values of

(f)

Plot a graph of

(g) (h)

Determine the slope, S, of your graph. Calculate the resistivity, ρ, of the wire from:

against l.

ρ = 1.6 x 10-5 S.

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.

535/3 UCE Physics Practical Experiments. 28. Experiment to determine the resistance of the filament of a torch bulb. In this experiment, you will determine the resistance, S, of the filament of the torch bulb provided. (a) Fix the bare wire, P, on the bench using pieces of cello tape.

(b) (c) (d) (e) (f) (g) (h) (i)

Connect the circuit as shown in the figure above. Starting with length, x0 = 1.0 and x = 0.2 m, close the switch, K. Read and record the voltmeter reading, V, and the ammeter reading, I. Open the switch, K. Repeat procedures (b) to (e) for values of x = 0.3, 0.4, 0.5, 0.6 and 0.7 m. Record your results in a suitable table. Plot a graph of, V (along vertical axis) against I (along horizontal axis). Determine the slope, S, of the graph.

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535/3 UCE Physics Practical Experiments. 29. Experiment to determine the internal resistance of a dry cell. In this experiment, you will determine the internal resistance of the dry cell provided. (a) Connect the circuit shown in the figure below.

(b) Close switch K. (c) Record the voltmeter reading, E. (d) Disconnect the circuit and connect the circuit shown in Fig. 4 below, with lo = 1.00m

(e) (f) (g) (h) (i) (j) (k) (l)

Starting with length l = 0.100m, close the switch, K. Record the voltmeter reading, V. Open switch, K. Repeat the procedure from (e) to (g) for values of l = 0.200, 0.300, 0.400, 0.500, 0.600 and 0.700m. Record your results in a suitable table. Plot a graph of V (along the vertical axis) against l (along the horizontal axis). Find the slope, S of the graph. Calculate the internal resistance, r, of the cell from the expression: r = 3.7 (

– lo )

DISMANTLE THE SET UP

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535/3 UCE Physics Practical Experiments. 30. Experiment to determine the constant of a bare wire. In this experiment, you will determine a constant, γ, of the bare wire, W, provided. (a) Record the diameter, d, of the bare wire provided. (b) Calculate the constant, γ, from, γ =

(c) (d) (e) (f) (g) (h) (i)

.

Fix the bare wire, W, provided on the metre rule using cello tape. Connect the circuit shown in the figure above. Starting with length l = 0.200 m, close switch, K. Read and record the readings V and I of the voltmeter and ammeter respectively. Open switch, K. Repeat procedures (e) to (g) for values of l = 0.300, 0.400, 0.500, 0.600, and 0.700 m. V Tabulate your results in a suitable table including values of /I. V

(j) Plot a graph of /I (along the vertical axis) against length l (along the horizontal axis). (k) Find the slope, S, of your graph. (l) Find the constant, γ, of the bare wire, W, from:

γ=

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535/3 UCE Physics Practical Experiments. 31. Experiment to determine the internal resistance of cells. In this experiment, you will determine the internal resistance r of the cells provided. (a) Record the resistance RS of the resistor R. (b) Connect the two dry cells in series across the voltmeter and record the reading V0 of the voltmeter. (c) Fix the bare wire P provided on the bench using cello tape.

(d) (e) (f) (g) (h)

Connect the circuit as shown in the figure above, starting with a length x = 0.200 m. Close switch K. Record the reading I of the ammeter. Open switch K. Repeat procedures in (d) to (g) for values of x = 0.300, 0.400,0.500, 0.600 and 0.700 m.

(i) Record your results in a suitable table including values of and . (j) Plot a graph of

against .

(k) Find the intercept C on the

– axis.

(l) Calculate the internal resistance r from the expression: r = V0C – RS.

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535/3 UCE Physics Practical Experiments. 32. Experiment to determine the resistivity of the material of a wire. In this experiment, you will determine the resistivity, ρ, of the material of the wire provided.

(a) Connect the circuit as shown in the figure above. (b) With the switch, K, open, adjust the position of the jockey along the bare wire such that l = 0.2 m. (c) Close switch K. (d) Note the ammeter reading, I and voltmeter reading V. (e) Open switch K. (f) Repeat procedures (b) to (e) for values of l = 0.30, 0.40, 0.50, 0.60 and 0.70 m. (g) Enter your results in a suitable table including values of . (h) Plot a graph of

against l.

(i) Find the slope, S, of the graph. (j) Calculate the resistivity, ρ, of the material of the bare wire from the expression: ρ = 2.04 x 10-7S.

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535/3 UCE Physics Practical Experiments. 33. Experiment to determine the diameter of a bare wire. In this experiment, you will determine the diameter, d, of the bare wire provided.

(a) (b) (c) (d) (e) (f) (g)

Fix the bare wire on the table using cello tape. Set up the circuit as shown in figure 3. Adjust the position of the crocodile clips such that l = 0.85m. Close the switch K, Note the voltmeter reading V and the ammeter reading I. Open switch K. Repeat procedures (b) to (e) for values of l = 0.75, 0.65, 0.55, 0.45, and 0.35m.

(h) Enter your results in a suitable table including values of (i) Plot a graph of

against

and .

.

(j) Find the slope, S, of the graph. (k) Calculate the diameter of the bare wire, d, from the expression: 4.90x 10-7 =

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535/3 UCE Physics Practical Experiments. 34. Experiment to determine the resistivity of a wire. In this experiment, you will determine the resistivity, ρ, of the wire labeled P. (a) Connect the circuit shown below starting with length l = 0.100m.

(b) (c) (d) (e) (f)

Record the value Vo of the voltmeter. Close switch K. Read and record the ammeter reading I. Open switch K. Repeat procedure (c) to (e) for values of l = 0.200, 0.300, 0.400, 0.500, 0.600, 0.700, 0.800, and 0.900 m.

(g) Tabulate your results including values of . (h) Plot a graph of

against l.

(i) Determine the slope S1 of your graph. (j) Determine the mean diameter, d, in meters of wire P. (k) Find the value of ρ =

.

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