1.Easy
A stone is dropped from rest from a bridge 20 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 = 20 mg = 9.81 m/s²
t = s
Kinematics worksheet with answers
2.Easy
A car moving at 8 m/s speeds up with a constant acceleration of 3 m/s² for 9 s. How far does it travel in that time? Find s.
v₀ = 8 m/sa = 3 m/s²t = 9 s
s = m
3.Medium
A driver moving at 120 km/h sees an obstacle. Her reaction time is 1.1 s, after which the car brakes with a constant deceleration of 8 m/s². Find the total stopping distance d from the moment she sees the obstacle.
v₀ = 120 km/htr = 1.1 sa = −8 m/s²
d = m
4.Medium
A driver moving at 72 km/h sees an obstacle. Her reaction time is 1 s, after which the car brakes with a constant deceleration of 7.5 m/s². Find the total stopping distance d from the moment she sees the obstacle.
v₀ = 72 km/htr = 1 sa = −7.5 m/s²
d = m
5.Hard
Ball A is dropped from rest from a height of 55 m. At the same instant ball B is thrown straight up from the ground directly below at 18 m/s. Ignore air resistance and use g = 9.81 m/s². When do the balls meet? Find t.
H = 55 mv0B = 18 m/sg = 9.81 m/s²
t = s
6.Hard
Ball A is dropped from rest from a height of 55 m. At the same instant ball B is thrown straight up from the ground directly below at 23 m/s. Ignore air resistance and use g = 9.81 m/s². When do the balls meet? Find t.
H = 55 mv0B = 23 m/sg = 9.81 m/s²
t = s
Answer key
- 1. t = 2.019 s
- 2. s = 193.5 m
- 3. d = 106.1 m
- 4. d = 46.67 m
- 5. t = 3.056 s
- 6. t = 2.391 s
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