In 2016 there were 2025 reported collisions between trains and cars that’s resulted in 265 fatalities. Explain the change in kinetic energy as it relates to conservation of momentum

Avery hard rubber ball (m = 0.5 kg) is falling vertically at 4 m/s just before it bounces on the floor. the ball rebounds back at essentially the same speed. if the collision with the floor lasts 0.05 s, what is the average force exerted by the floor on the ball?

Asmall grinding wheel has a moment of inertia of 4.0×10−5 kg⋅m2 . what net torque must be applied to the wheel for its angular acceleration to be 150 rad/s2 ?

A1000-kg car is moving at 30 m/s around a horizontal unbanked curve whose diameter is 0.20 km. what is the magnitude of the friction force required to keep the car from sliding?