Arailroad freight car, mass 15 000 kg, is allowed to coast along a level track at a speed of 2.0 m/s. it collides and couples with a 50 000-kg loaded second car, initially at rest and with brakes released. what percentage of the initial kinetic energy of the 15 000-kg car is preserved in the two-coupled cars after collision

23.0760769 %

Explanation:

= Mass of freight car = 15000 kg

= Mass of second car = 50000 kg

= Velocity of freight car = 2 m/s

= Velocity of second car = 0

v = Combined mass velocity

As the linear momentum of the system is conserved we have

The initial kinetic energy

Final kinetic energy

The percentage is given by

The change in percentage of initial kinetic energy is 23.0760769 %

hey , the answer is c