O-LevelPhysicsKinematics5054/21 · Oct/Nov 2020 · Q18 Marks

Fig. 1.1 is the distance-time graph for a skydiver who jumps from a balloon at time t = 0. [Figure 1.1]

(a)(i)Describe the motion of the skydiver between t = 0 and t = 20s.[2]
(a)(ii)Explain the motion of the skydiver between t = 0 and t = 20 s in terms of the forces acting on him.[3]
(b)Using Fig. 1.1, determine the terminal velocity of the skydiver. On Fig. 1.1, indicate any values used for your calculation.[3]

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.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2020). The mark or mark type is shown in brackets.

[B1] accelerating or increasing speed
[B1] decreasing acceleration or speed increasing at a decreasing rate or reaches a constant speed
[B1] initially acceleration is due to force of gravity/weight (only) or force of gravity / weight larger than air resistance from (t = 0 to ≈ 7 s)
[B1] air resistance increases (with speed)
[B1] resultant force decreases / becomes zero or forces balance or air resistance equals weight
[C1] two different pairs of co-ordinates from straight-line section of graph seen
[C1] correct use of co-ordinates in a division
[A1] 48-52 m/s

On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.