# Physics Chapter 4 | 1st Year

# Chapter 4 Notes | Physics 1st Year

## “Work And Energy”

- Define the term work. Also derive the expression of work done by a variable force.
- Show that the work done in earth’s gravitational field is independent of path followed.
- Show that work done in a close path is zero or Show that earth’s gravitational field is conservative field.
- Define the term power. Show that power is the dot product of force and velocity.
- Show that 1kWh = 3.6 MJ.
- Define the term energy. Describe the different types of mechanical energy.
- State the work energy principle. Also derive it mathematical form.
- What do you know about absolute potential energy? Also derive its expression.
- Define the term escape velocity. Also derive its expression.
- Describe the inter-conversation of potential energy into kinetic energy for a free falling object.
- State the law of conservation of energy.