During a test, a motorcycle and rider have a combined mass of 250 kg. The motorcycle brakes from 20 m/s and comes to rest over a distance of 25 m. The braking force is constant. What is the braking force?
1000 N1000\ \mathrm{N}1000 N
4000 N4000\ \mathrm{N}4000 N
2500 N2500\ \mathrm{N}2500 N
2000 N2000\ \mathrm{N}2000 N