Answer:
17.7 m/s
Explanation:
Given:
y₀ = 0 m
y = 16 m
v₀ = 0 m/s
a = 9.8 m/s²
Find: v
v² = v₀² + 2a (y − y₀)
v² = (0 m/s)² + 2 (9.8 m/s²) (16 m − 0 m)
v = 17.7 m/s
The ball is moving at a speed of 17.7 m/s when it hits the ground.
Answer: 1.28 sec
Explanation:
Assuming that the glow following the collision was produced instantaneously, as the light propagates in a straight line from Moon to the Earth at a constant speed, we can get the time traveled by the light applying velocity definition as follows:
V = ∆x / ∆t
Solving for ∆t, we have:
∆t = ∆x/v = ∆x/c = 3.84 108 m / 3.8 108 m/s = 1.28 sec
