- Work is done when a force moves an object or changes its direction. It is measured in Joules.
- Rule for Work
Work (joules) = Force (newtons) × Distance (metres)
- Example to calculate Work
Question: A weightlifter raises weights of 2000 newtons from the floor to a height of 2 metres. How much work has been done?
|Work|| = Force × Distance|
|= 2000 N × 2 m|
|= 4000 J (joules)|
- Power is the rate at which work is done. Power is measured in Watts.
|Power (watts) = ||Work (joules)|
- Example of calculating Power
Question: A weightlifter lifted 2000 newtons to a height of 2 metres. This was 4000 joules of work. What is the power output if this was done for 2 seconds?
|Power = ||Work|| = ||4000 J|| = 2000 W (watts)|