Answer to Question #69011 in Mechanics | Relativity for Caroline

Question

Caroline Rivera
Dwight uses a spring (k=70N/m) on a horizontal surface to make a launcher for model cars. The spring is attached to a holder that has a mass of 0.3kg. If he compresses the spring and releases it, the launcher will move back and fourth in periodic motion.

If he compresses the spring by 0.4m and releases it, what is the acceleration of the launcher as it reaches it natural length

Answer 1

When the spring is compressed it stores a potential energy, which is transformed in to the kinetic energy of the holder when the spring is released. When the launcher reaches it neutral length it can no longer act with any force on the holder, and so the acceleration will be equal to
a=F/m=0