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Define gravitational potential energy

31/10/2023 at 12:39 pm (last edited 31/10/2023 at 12:39 pm)

Gravitational potential energy is the energy a body has due to its height above ground.

Define kinetic energy

31/10/2023 at 12:38 pm (last edited 31/10/2023 at 12:38 pm)

Kinetic energy is the energy a body in motion possesses.

Define energy

31/10/2023 at 12:36 pm (last edited 31/10/2023 at 12:36 pm)

Energy is the ability to do work.

Define power

31/10/2023 at 12:34 pm (last edited 31/10/2023 at 12:35 pm)

Power is the rate of work done, or the rate of energy conversion.

Define work done

31/10/2023 at 12:33 pm (last edited 31/10/2023 at 12:33 pm)

Work done is the product of a force, and the distance moved by the body, in the direction of the force.

Define atmospheric pressure

30/10/2023 at 10:08 pm (last edited 30/10/2023 at 10:08 pm)

Atmospheric pressure is the force per unit area exerted by an atmospheric column of air above a particular point.

Atmospheric pressure at sea level (1 P_atm) is:

76cm Hg or 760mm Hg, or
101.3kPa or approx. 10⁵ Pa

Define pressure

30/10/2023 at 9:42 pm (last edited 30/10/2023 at 9:42 pm)

Pressure is force acting perpendicularly per unit area of a surface.

Define Principle of Moments

30/10/2023 at 9:28 pm (last edited 30/10/2023 at 9:28 pm)

The Principle of Moments states that, when a body is in equilibrium, the sum of the clockwise moments about a pivot is equal to the sum of the anti-clockwise moments about the same pivot.

Define centre of gravity

30/10/2023 at 9:25 pm (last edited 30/10/2023 at 9:25 pm)

The centre of gravity is the point which the whole weight of an object appears to act on, for any orientation of the object.

Define moment of a force

30/10/2023 at 9:24 pm (last edited 30/10/2023 at 9:24 pm)

The moment of a force is the turning effect of a force, and is obtained by the product of the force and the perpendicular distance from the line of action of the force to the pivot.