CSEC Integrated Science Paper 3 May/June 2008 - Free CXC Past Paper with Answers

Two pieces of apparatus are provided, one as shown in Figure 1 and the second is similar with a rubber band instead of the spring. You will also be provided with a series of masses (weights): 10 g, 20 g, 30 g ... to 100 g. The elasticity of two materials, a spring and a rubber band are to be compared.

Complete Table 1 by measuring the original length of EACH material, that is, the length without any load attached.

Assume that the mass of each material without any load is zero grams (0 g). Complete Table 2 by performing the steps below. (i) Record the original length of the spring. (ii) Attach a 10 g mass (weight) to (or place it in) the hanger that is attached to the spring. (iii) Measure the new length of the spring and record this. (iv) Calculate the extension of the spring for this 10 g mass (weight) (new length – previous length) and record this. (v) Remove this mass (weight). Attach the next mass (weight) in the series to (or place it in) the hanger. (vi) Repeat steps from (ii) to (iv) until all the masses (weights) in the series have been used. (vii) Repeat the steps from (i) to (vi) for the hanger attached to the rubber band.

In Figure 2 on page 5, plot, on the same axes a line graph of extension against mass/load for (i) the spring (ii) the rubber band.

Note: The mass/load is on the horizontal (x) axis. Use an appropriate scale for the vertical (y) axis.

Label your line graphs and Figure 2 appropriately.

Extension per gram = greatest extension $\div$ greatest load Calculate the extension per gram for

Deduce which material is more elastic.

Refer to Table 2 and identify ONE dependent variable.

State the step(s) you would take in order to compare the elasticity of a third material.

You are provided with a whole Irish potato (white potato), six strips of Irish potato of different lengths, tap water, brine and a ruler.

Make a large drawing of a whole potato in the space provided in Figure 3.

Write a title for this drawing. Title

State the magnification. Magnification:

TABLE 3: COMPARISON OF POTATO STRIPS

Measure the strips of potato and record your answers in Table 3.

Place THREE strips of potato (at the same time) in brine for 20 minutes.

Measure the length of EACH strip after 20 minutes and record the length in Table 3.

Calculate the change in length after 20 minutes for EACH strip.

Repeat the steps from (ii) to (iv) with tap water.

In the space provided in Figure 4, make a drawing of the actual size of strips 2 and 3 of the potato after 20 minutes.

What patterns were observed with changes in length and type of medium?

Explain any observed change(s) in the lengths of the potato strips.

Which variable was controlled for Strips 1, 2, 3, 4, 5 and 6?

Identify ONE manipulated variable.

Suggest ONE reason for using three strips in the same type of medium.

CSEC Integrated Science Paper 3 May/June 2008 Questions

Question 1 (17 marks)

Question 2 (18 marks)