frictionless loop?

Question

a block of mass sliding without friction along a single looped track is to remain on the track at all times, even at the very top of the loop radius.
A) in terms of the given quantities, determine the minimum release height. Next if the actual release hight is 2h, calculate (B) the normal force exerted by the track at the bottom of the loop, (C) the normal force exerted by the track at the loop's top and (D) the normal force exerted by the track after the block exits the loop onto the flat section. note: the mass is under the top of the loop.

Answer 1

You haven't provided the "given quantities," so nobody here can solve this for you. Here is one tip, though. Check the speed at the top or bottom of the loop, and determine the centripetal acceleration using v^2 / r. That force has to be equal to the linear combination of gravity and the normal force, which act in the same direction at the top of the loop, but in opposite directions at the bottom, because gravity is always down while the normal force is towards the center of the loop, as is the net centripetal force. That's how you can find the normal force at different points.