CAIE Physics (9702)

In this experiment, you will investigate the oscillations of a pendulum on a board. in Fig. 1.1. adhesive putty nail board string bob The length L of the pendulum is the distance between the centre of the nail and the centre of the bob. Adjust the length of the pendulum by wrapping the string around the nail so that the centre of the bob is approximately 1.5 cm from the edge of the board. S = cm L = cm [1] * 0000800000002 * clamp nail stringbob adhesive putty stand boss bench board shown in Fig. 1.2. Adjust the position of the boss so that h is approximately 22 cm. h = cm T = s [2] * 0000800000003 *

Change h in the range 10.0 cm G h G 38.0 cm and determine T. Repeat until you have six sets of values of h and T. Record your results in a table. Include values of and T in your table.

(i) Plot a graph of T on the y-axis against on the x-axis.

Draw the straight line of best fit.

Determine the gradient and y-intercept of this line. gradient = y-intercept = [2] * 0000800000004 *

(i) It is suggested that the quantities T, S and h are related by the equation= A+ B where A and B are constants. Using your answers in (d)(iii), determine the values of A and B. Give appropriate units. A = B =

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Theory suggests thatA =28π where g is the acceleration of free fall. Use your values in (a) and (e)(i) to determine a value for g. Give an appropriate unit. g = [1] [Total: 20] * 0000800000006 * BLANK PAGE * 0000800000007 * You may not need to use all of the materials provided.

In this experiment, you will investigate the resistance of a light-dependent resistor (LDR) using the light from a light-emitting diode (LED).LEDF Q 3 V d.c. wire W LED are connected as shown in Fig. 2.1. wire W between P and Q. Ωohmmeter LDR Fig. 2.2 * 0000800000008 * stand boss benchLED to LED circuit to ohmmeterLDR clamp component holder component holder Fig. 2.3 (not to scale) Adjust the position of the LDR so that d is approximately 0.03 m. d = m

Estimate the percentage uncertainty in your value of d. Show your working. percentage uncertainty = % [1] * 0000800000009 * Measure and record L. L = The resistance R of the LDR is given by the ohmmeter . Measure and record V and R. V = R = [2] L = V = R =

It is suggested that the relationship between V, d and R isV =+ k where Z has the value 1.00 × 10 V Ω m and k is a constant.

Using your data, calculate two values of k. first value of k = second value of k = [1] * 0000800000010 * [ 2

Justify the number of significant figures that you have given for your values of k.

It is suggested that the percentage uncertainty in the values of k is 5%. Using this uncertainty , explain whether your results support the relationship in (d).

It is suggested thatk = where h is 6.63 × 10-34 J s, c is 3.00 × 10m s e is 1.60 × 10-19 C and λ is the wavelength of the light emitted by the LED. Use your second value of k to determine λ . λ = m [1] * 0000800000011 * [[2 Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable ef fort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cambridgeinternational.org after the live examination series. Local Examinations Syndicate (UCLES), which is a department of the University of Cambridge.

(i) Describe four sources of uncertainty or limitations of the procedure for this experiment. For any uncertainties in measurement that you describe, you should state the quantity being measured and a reason for the uncertainty. 1 2 3 4

Describe four improvements that could be made to this experiment. You may suggest the use of other apparatus or different procedures. 1 2 3 4 [4] [Total: 20] * 0000800000012 * [T2