Answer:
280 J
Explanation:
According to the work-energy theorem, the work done on an object (W) is equal to the change in kinetic energy (ΔKE). The kinetic energy (KE) is half the mass (m) times the square of the speed (v).
W = ΔKE
W = ½ mv² − ½ mv₀²
W = ½ m (v² − v₀²)
Plug in values:
W = ½ (0.015 kg) [ (350 m/s)² − (400 m/s)² ]
W = -281.25 J
Rounded to two significant figures, the window does 280 J of work on the bullet, meaning the bullet also does 280 J of work on the window.
