posted by Mariam .
A 250 g block is dropped onto a relaxed vertical spring that has a spring constant of k= 2.5 N/cm. The block becomes attached to the spring and compresses the spring 12 cm before momentarily stopping. While the spring is being compressed,
(a) what work is done on the block by the gravitational force on it?
(b) what work is done on the block by the spring force?
(c) what is the speed of the block just before it hits the spring? (neglect friction).