Grade 11 physics definitions Chapter 7 Work, Energy, Power Flashcards
1 Joule
One joule is the amount of energy gained by a body when a resultant force of 1 Newton moves it a displacement of 1meter in the direction of the force.
Work
The work done on a body is the product of the force and the displacement of the body in the direction of the applied force. (The work done on a body is a scalar quantity.)
Work-energy theorem
The work done by a resultant force on an object is equal to the change in its kinetic energy.
Energy
Energy is the ability to do work.
Potential energy
The potential (gravitational) energy is the energy that a body has by virtue of its height above the ground.
Principle of conservation of energy
The total energy of an isolated system remains constant. (Energy cannot be created or destroyed. It can only be transferred from one type of energy into another type.)
Principle of conservation of mechanical energy
The sum of the gravitational potential energy and the kinetic energy remains constant during free fall (in the absence or air resistance or any external forces.)
Power
Power is the rate at which energy is transferred (or the rate at which work is done.)
One watt (1W)
1W of power is delivered when 1J of energy is transferred per second.
