A student investigates a falling mass. The student uses the apparatus shown in Fig. 3.1. [Figure 3.1]

1. (a)(i)The bottom of mass hanger A is at a height h above the floor as shown in Fig. 3.1. The student places one end of a metre rule on the floor and the other end near to the mass hanger. The top of the metre rule is shown in Fig. 3.2. [Figure 3.2] Record h. h = ..................................................... cm[1]
2. (a)(ii)Describe one source of error when measuring h and suggest one improvement to the procedure to reduce this error. source of error 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3. (b)(i)The student places a mass m = 5.0g on mass hanger A. The additional mass causes the mass hanger to descend slowly. The student uses a stop-watch to take three readings of the time taken for mass hanger A to fall to the floor. Using the stop-watch readings in Fig. 3.3, determine an accurate average time t_av for the mass hanger to descend the height h. [Figure 3.3] Show your working. t_av = ..................................................... s[2]
4. (b)(ii)The student repeats the time measurements with different masses placed on hanger A. Record the measurements from (b)(i), in Table 3.1. Complete the headings and give units. [Table 3.1] | mass m on hanger | | average time t_av | | | :--------------- | :----- | :---------------- | :----- | | | | | | | 5.0 | | | | | 7.0 | 4.03 | 4.40 | 4.09 | 4.2 | | 9.0 | 3.06 | 2.93 | 3.09 | 3.0 | | 11.0 | 2.50 | 2.59 | 2.56 | 2.6 | | 13.0 | 2.13 | 2.28 | 2.28 | 2.2 |[3]
5. (c)On the grid provided on page 11, plot a graph of average time t_av on the y-axis against the mass m on the x-axis. Draw the best-fit curve.[4]
6. (d)Describe the relationship between t_av and m shown by the graph.[2]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.