A-level · Kinematics

Vertical motion under gravityExam-style questions

Why an object moving freely under gravity is just a constant-acceleration problem with a = ±g, how to choose a positive direction and translate "thrown up", "returns", "hits the ground" into suvat values, and why the up-and-down trip makes distance and displacement differ.

Start practising Read the lesson

13 questions · A-level level · mark scheme and worked solution on each · no sign-up to try

DifficultyAll Level 2 Level 3 Level 4

1
A ball is dropped from rest. Find its speed after $2$ s. ( $g = 9.8$ .)
Level 2 · 2 marksTry it
2
A stone is dropped from rest. Find the distance it falls in $3$ s. ( $g = 9.8$ .)
Level 2 · 2 marksTry it
3
A hot-air balloon is held at rest at a height of $22.5$ m above horizontal ground. A sandbag of mass $3$ kg is released from rest from the balloon and falls vertically to the ground.

The sandbag is modelled as a particle. In a first model, air resistance is ignored.
(a) Using the first model, find how long the sandbag takes to fall to the ground.

(3 marks)

The sandbag actually takes $2.5$ s to reach the ground. In a second model, the motion of the sandbag is opposed by air resistance, which is modelled as a constant force of magnitude $R$ newtons.
(b) Using the second model and the time of $2.5$ s, find $R$ .

(5 marks)
Level 3 · 8 marksTry it
4
A small ball is thrown vertically upwards from a point $A$ at the edge of a diving platform, $10$ m above the surface of the water in a swimming pool. The ball leaves $A$ with speed $U\ \text{m s}^{-1}$

On its way down, the ball misses the platform and falls into the pool. It reaches the surface of the water $2$ s after it was thrown.

The ball is modelled as a particle moving freely under gravity.
(a) Find the value of $U$ .

(3 marks)
(b) Find the speed of the ball at the instant it reaches the surface of the water.

(3 marks)
(c) Sketch a speed-time graph for the motion of the ball from the instant it is thrown to the instant it reaches the surface of the water.

(No further calculations are required.)

(2 marks)
Level 3 · 8 marksTry it
5
A ball is thrown vertically upwards at $14.7\ \text{m s}^{-1}$ . Find the time to reach its highest point. ( $g = 9.8$ .)
Level 3 · 2 marksTry it

8 more questions on vertical motion under gravity

Free with an account — just an email, no card. The whole bank, every mark scheme and worked solution.

Start free