A student collects measurements in order to find a value for the acceleration of free fall. Part of the setup is shown in Fig. 4.1. The student records the vertical distance $d$ from the underside of the electromagnet to the bench. The time $t$ for an iron ball to drop from the electromagnet to the bench is also recorded. Matching values of $t^2$ and $d$ are given in Fig. 4.2.
(a)[1]
On Fig. 4.2, draw the line of best fit through the points.
(b)[2]
State and explain why the graph in Fig. 4.2 has a non-zero intercept.
(c(i))[1]
Work out the student’s value for the diameter of the ball.
(c(ii))[3]
Work out the student’s value for the acceleration of free fall.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Correct straight line drawn passing through every plotted point” …