A 0.5 kg air-hockey puck is initially at rest. What will its kinetic energy be after a net force of 0.4 N acts on it for a distance of 0.7 m?

0.28 J

Explanation:

Since the air-hockey puck was initially at rest

KE₀ = initial kinetic energy of the air-hockey puck = 0 J

KE = final kinetic energy of the air-hockey puck

m = mass of air-hockey puck 0.5 kg

F = net force = 0.4 N

d = distance moved = 0.7 m

Using work-change in kinetic energy

F d = (KE - KE₀)

(0.4) (0.7) = KE - 0

KE = 0.28 J