What can keep ice from melting

A train is moving on horizontal rails with a uniform acceleration 5m/s2. a passenger siiting in a boggie drpos a stone inside the boggie. what will be the acceleration of stone wrt the rails?

How many electrons flow through the hair dryer in 5.0 min?

1. A ball bouncing against the ground and rebounding is an example of an elastic collision. Describe two different methods of evaluating this interaction, one for which momentum is conserved, and one for which momentum is not conserved.

A bullet of mass 20g strikes a block of mass 980g with a velocity u and gets embedded in it. The block is in contact with a spring whose force constant is 100N/m. After the collision the spring is compressed to 10cm. Find: 1.

Using energy considerations, calculate the average force (in N) a 70.0 kg sprinter exerts backward on the track to accelerate from 2.00 to 9.00 m/s in a distance of 25.0 m, if he encounters a headwind that exerts an average force of 30.

Definition of artficial and natural radioactivity

In order for an object to conserve it's total mechanical energy it is absolutely necessary that?

Your body is presently converting chemical potential energy from food into thermal energy at a rate of about 100 J/s, or 100 W. If heat were flowing out of you at a rate of about 200 W, would your body temperature go up or down?

Which energy depends the arbitrarily assigned zero level

What is a transverse wave