Arunaway railroad car, with mass 30x10^4 kg, coasts across a level track at 2.0 m/s when it collides with a spring loaded bumper at the end of the track. if the spring constant of the bumper is 2x10^6 n/m, what is the maximum compression of the spring during the collision? (assume collision is elastic)

0.775 m

Explanation:

As the car collides with the bumper, all the kinetic energy of the car (K) is converted into elastic potential energy of the bumper (U):

where we have

is the spring constant of the bumper

x is the maximum compression of the bumper

is the mass of the car

is the speed of the car

Solving for x, we find the maximum compression of the spring:

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