Work+and+power

IGCSE PHYSICS > Energy resources and energy transfer =Work and power=

4.9 recall and use the relationship between work, force and distance moved in the direction of the force

WORK AND ENERGY: The work done is a measure of the amount of energy transferred.

work done = force × distance moved W = F × d 4.10 understand that work done is equal to energy transferred

JOULE (J): The unit of work and energy. 1 joule is the work done when a force of 1 newton moves through 1 metre. 1J = 1Nm GRAVITATIONAL POTENTIAL ENERGY: Energy which an object has due to its position in a gravitational field. KINETIC ENERGY: Energy which an object has due to its motion. 4.11 recall and use the relationship:

gravitational potential energy = mass × g × height GPE = m × g × h

4.12 recall and use the relationship:

4.13 understand how conservation of energy produces a link between potential energy, kinetic energy and work 4.14 describe power as the rate of transfer of energy or the rate of doing work 4.15 use the relationship between power, work done (energy transferred) and time taken POWER: The rate of doing work or the rate of transferring work from one form to another. WATT: The unit of power. 1 watt = 1 joule per second.

PRACTICE QUESTIONS FOR ENERGY, WORK AND POWER CALCULATIONS: [|Practice qs on Energy, Work and Power Calculations.doc]