1.Easy
A stone is dropped from rest from a bridge 10 m above the water. Ignore air resistance and use g = 9.81 m/s². How long does it take to reach the water? Find t.
v₀ = 0h = 10 mg = 9.81 m/s²
t = s
Kinematics worksheet with answers
2.Easy
A train slows down uniformly from 16 m/s to 7 m/s in 18 s. How far does it travel in that time? Find s.
v₀ = 16 m/sv = 7 m/st = 18 s
s = m
3.Medium
A car speeding at a constant 35 m/s passes a police car standing still. At that moment the police car starts and accelerates uniformly at 5.5 m/s². How far from its starting point does the police car catch up? Find d.
vcar = 35 m/sapolice = 5.5 m/s²v0,police = 0
d = m
4.Medium
A driver moving at 100 km/h sees an obstacle. Her reaction time is 0.8 s, after which the car brakes with a constant deceleration of 4.5 m/s². Find the total stopping distance d from the moment she sees the obstacle.
v₀ = 100 km/htr = 0.8 sa = −4.5 m/s²
d = m
5.Hard
A model rocket is launched straight up from rest. Its engine gives it a constant upward acceleration of 32 m/s² for 2.5 s, after which the engine stops and the rocket moves freely. Ignore air resistance and use g = 9.81 m/s². How long after launch does it hit the ground? Find t.
a = 32 m/s²t1 = 2.5 sg = 9.81 m/s²
t = s
6.Hard
A model rocket is launched straight up from rest. Its engine gives it a constant upward acceleration of 32 m/s² for 1.5 s, after which the engine stops and the rocket moves freely. Ignore air resistance and use g = 9.81 m/s². Find the greatest height hmax the rocket reaches.
a = 32 m/s²t1 = 1.5 sg = 9.81 m/s²
hmax = m
Answer key
- 1. t = 1.428 s
- 2. s = 207 m
- 3. d = 445.5 m
- 4. d = 108 m
- 5. t = 19.98 s
- 6. hmax = 153.4 m
Full step-by-step solutions: practise this topic on examproblems.com.