TOPIC 3: Vertical projectile motion in one dimension 1.
GRADE 12: WORKSHEET
A boy stands on the edge of a cliff. He throws a stone vertically upwards with an initial
velocity of 12 m. st. The stone strikes the ground below the cliff after 4 s. Ignore air
resistance.
1.1
What is the magnitude and direction of the acceleration of the stone:
1.1.1 when it is moving upwards?
1.1.2 when it reaches its maximum height?
1.1.3 when it is falling down?
1.2 At what time(s) does the stone have a speed of 3 m. s-1?
1.3 How long does the stone take to reach its maximum height?
1.4 Determine the height of the cliff.
In an experiment, a learner drops a brick A from a height of 8 m. After 0.6 s another
learner throws a second brick B downwards from the same height. Both bricks A and B,
hit the ground at the same time. Ignore the effects of friction and calculate the speed at
which brick B was thrown.
2.​