Question 111 marks
Question
In this experiment, you will investigate the stretching of a spring. Carry out the following instructions, referring to Fig. 1.1. spring metre ruler clamp stand bench Fig. 1.1 (a) The metre ruler is clamped in position near to the spring. Do not change the position of the metre ruler. (i) The value l0 is the length of the spring when the load L is 0.0 N. Measure the unstretched length l0 of the spring. Do not include the loops at the ends of the spring in your measurement. Record l0 in cm to the nearest mm in Table 1.1. [1] (ii) Draw a diagram of the spring to show clearly the length l0 of the spring. [1] (b) • Suspend a load L = 1.0 N from the spring. • Record the new length l of the spring in Table 1.1. • Calculate the extension e of the spring using the equation e = (l – l0). • Record the value of e in Table 1.1. • Repeat the procedure using loads L = 2.0 N, 3.0 N, 4.0 N and 5.0 N. • Record all the readings and results in Table 1.1. Table 1.1 L/N l / cm e / cm 0.0 0 1.0 2.0 3.0 4.0 5.0 [3] (c) Plot a graph of L / N (y-axis) against e / cm (x-axis). Draw the best-fit line. [4] (d) Use the graph to determine eA, the extension produced by a load of 2.5 N. Show clearly on the graph how you obtained the necessary information. eA = …… [2] [Total: 11]
Mark scheme
1(a)(i) realistic value of l0 in centimetres to the nearest mm 1 1(a)(ii) diagram clearly showing the distance l0 1 1(b) increasing values of l for loads from 1 N to 5 N 1 all greater than l0 1 correct e values 1 1(c) graph: 1 axes correctly labelled with quantity and unit and the right way round suitable scales filling ≥ ½ the grid between the extreme plotted points 1 six plots correct to ½ small square – origin must be included 1 good line judgement, thin, continuous line 1 1(d) method shown clearly on graph 1 value correct to ½ small square – unit needed 1