# Speed of object after it is ejected by a spring

A block of mass m slides without friction on a table with speed v. It hits and compresses a spring of force constant k by a distance l. The spring then expands again ejecting the block in the opposite direction as it was originally traveling. Neglecting the mass of the spring, what is the speed of the object after it is ejected by the spring?

v/2

2v

v

v - l*sqrt(k/m)

https://brainmass.com/physics/energy/speed-object-after-ejected-spring-116179

#### Solution Preview

The mass is moving without friction with a velocity v.

Then we can write the Kinetic energy possessed by the mass as, KE = 1/2 m v^2 = 0.5 m v^2

As per the law of conservation of ...

#### Solution Summary

Detailed explanation of the problem along with solution. The speed of the object after it is ejected by the spring is determined.

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