Answer:
397.51 kJ
Step-by-step explanation:
Since the change in velocity is done on a level road, there is no change in the potential energy. The workdone is the workdone on reducing the kinetic energy.
Workdone W = change in kinetic energy ∆K.E
W = ∆K.E
K.E = 0.5mv^2
∆K.E = 0.5m(m1^2 - m2^2)
Given;
Mass m = 2065 kg
Initial velocity v1 = 23.0 m/s
Final velocity v2 = 12.0 m/s
W = ∆K.E = 0.5m(m1^2 - m2^2)
Substituting the given values;
W = ∆K.E = 0.5×2065(23^2 - 12^2)
W = 397512.5J
W = 397.51 kJ