Question

1. What is the principle of conservation of energy? What types of energy could be involved? Under what conditions mights energy not be conserved?

2. Write out the formulas to define kinetic, gravitational potential and total mechanical energy.

3. When you define potential energy for a system, like position, you can choose where the zero is defined to be. Think about the set up you will use for a tilted air track. Where might be a logical position to define the zero of potential energy to be?

Answer 1

1.

principle of conservation of energy says that energy can neither be created nor be destroyed. it can only be converted from form to another form.

any type of energy like kinetic , potential , heat , light energy and so on can be involved in principle of conservation of energy.

This principle is not applicable if the environment around the things we are considering is changing.

2.

kinetic energy is the energy due to motion of an object and is given by the formula

KE = (0.5) m v² where m = mass of the object , v = speed of the object

Potential energy is the energy due to location of the object relative to a reference line and is given as

PE = mgh where m = mass of the object , h = height above the reference line

mechanical energy is the sum of kinetic energy and the potential energy.

mechanical energy = KE + PE