CAIE Physics (9702)

In this experiment, you will investigate an electrical circuit. You have been provided with a wooden strip with a wire attached.

Measure and record the length L of the wire between the nails on the wooden strip, as shown in Fig. 1.1. wooden strip wire nail nail L =

You have also been provided with a wire labelled A with crocodile clips at its ends. wooden strip wire A 1.5 V d.c. The distance between one of the nails and H is d, as shown in Fig. 1.2. Attach H to the wire on the wooden strip so that d is approximately 20 cm. and V d = = =

Increase d by placing H at different positions on the wire and record V and V Repeat until you have six sets of readings of d, V and V . Include your values from

. Record your results in a table. Include values of ( d and d in your table.

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

Draw the straight line of best fit.

Determine the gradient and y-intercept of this line. gradient = y-intercept =

It is suggested that the quantities V, V and d are related by the equation d = Pd+ Q where P and Q are constants. Using your answers in (d)(iii), determine values for P and Q. Give appropriate units. P = Q =

Wire A has the same length L as the wire between the nails. Theory suggests that P = - and Q = L. A student repeats the experiment using two shorter wires of equal length. Sketch a second line on the graph to show the expected results. Label this line W. [1] [Total: 20] You may not need to use all of the materials provided.

In this experiment, you will investigate the motion of two connected masses. You have been provided with two masses connected by a string. The larger mass is 100 g and the smaller mass is 10 g. bench stand boss rod of clamp string 100 g mass 10 g mass the 100 g mass is as close to the rod of the clamp as possible. The string should be resting on the rod of the clamp. When the 10 g mass is released, the 100 g mass will fall downwards. The 10 g mass will fall and move towards the stand. The string will wrap itself several times around the rod of the clamp. You may need to repeat the procedure several times before you see this result. Measure and record A. A =

Estimate the percentage uncertainty in your value of A. Show your working. percentage uncertainty = %

Fig. 2.3 shows the 10 g mass held so that the angle between the string and the vertical is θ. Measure and record θ and H. θ = ° H =

Calculate cos θ and cos θ = =

Repeat

with a value of θ of approximately 45°. θ = ° H = cos θ = =

It is suggested that the relationship between H, A and θ is = k cos θ + 1 where k is a constant.

Using your data, calculate two values of k. first value of k = second value of k =

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 20%. Using this uncertainty, explain whether your results support the suggested relationship in

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(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]