A 50.0 g toy car is released from rest on a frictionless track with a vertical loop of radius R (loop-the-loop). The initial height of the car is h = 4.00R.
a. What is the speed of the car at the top of the vertical loop?
b. What is the magnitude of the normal force acting on the car at the top of the vertical loop?

the speed of the car at the top of the vertical loop  

the magnitude of the normal force acting on the car at the top of the vertical loop  

Explanation:

Using the law of conservation of energy ;

The  magnitude of the normal force acting on the car at the top of the vertical loop can be calculated as:

you cant move and you feel like someones pushing you down onto your bed it can feel like you want to get up but you just can't it can be extremely scary

which three statements are true about all alloys?