A block of mass 500 g is placed on a horizontal surface near the foot of a slope and rests against a compressed spring of elastic constant 
. The spring is compressed by 20 cm and the slope is inclined at an angle 
to the horizontal. When the block is released, it slides towards and up the slope as shown in the figure below.
Figure 1: Block attached to a compressed spring.
What is the elastic energy of the compressed spring?
What is the initial kinetic energy of the block at the bottom of the slope?
With what speed does the block move away after the spring is released?
How far up the slope does the block go if friction is negligible?
How far up the slope does the block move if there is a friction of coefficient 0.1 between the block and the surface of the slope?
.
