Question

Calculate the change in kinetic energy of a 2.50kg cat slowing down from 1.00m/s to 0.500m/s.

Answer 1

KE change = 0.5M*V2^2 - 0.5M*V1^2 = 0.5M(V2^2 - V1^2).
V1 = 1 m/s.
V2 = 0.5 m/s.
Since the KE decreased, the change should be negative.