Physics Definitions

Front 1

Terminal velocity

Back 1

Constant velocity of a falling object when the net force is zero

Front 2

Newton’s first law of motion

Back 2

A body that is at rest continues to be at rest, and a body in motion continues to move with uniform velocity, unless a net external force acts on it.

Front 3

Newton’s second law of motion

Back 3

The rate of change of momentum of a body is directly proportional to the net force acting on it, and occurs in the direction of the net force.

Front 4

Newton’s third law

Back 4

If a body A exerts a force on body B, then body B exerts a force on body A of the same type and magnitude, but in the opposite direction.

Hint 4

If body A...

Front 5

Inertia

Back 5

Inertia of a body is its reluctance to start moving and reluctance to stop once it has begun moving.

Hint 5

Two cases

Front 6

Mass

Back 6

Mass is a measure of the inertia of an object.

Front 7

Weight

Back 7

The gravitational force acting on an object towards the centre of the Earth.

Front 8

Linear momentum

Back 8

p of an object is the product of its mass and its linear velocity.

Front 9

Impulse

Back 9

Impulse is the product of the force acing on an object and the duration over which it acts.

Front 10

Conservation of linear momentum

Back 10

The total linear momentum of a system remains constant provided that no net external force acts on it.

Front 11

Elastic

Back 11

A perfectly elastic collision is one where the total kinetic energy is conserved.

Front 12

RSOS = RSOA

Back 12

Derived from conservation of KE and of momentum. Get a difference of squares equation, then divide KE equation by momentum equation.

Front 13

Field of force

Back 13

Region of space in which an object can exert a force on certain bodies not in contact with it.

Front 14

Electric field

Back 14

Region of space in which a stationary charge will experience an electrical force.

Front 15

Gravitational field

Back 15

Region of space where a force acts on a mass.

Front 16

Magnetic field

Back 16

Region of space where a force acts on a moving charge or a magnet.

Front 17

Frictional force

Back 17

Force that opposes motion between two surfaces in contact.

Front 18

Viscous force

Back 18

Resistive force that an object experiences when it moves through a fluid.

Hint 18

Fluid

Front 19

Tension

Back 19

Force exerted by a string or cable when it is pulled tight by opposite ends.

Front 20

Hooke’s law

Back 20

The magnitude of force exerted by a spring on an object attached to it is directly proportional to the length of extension from equilibrium, given that the elastic limit of the spring is not exceeded.

Front 21

Pressure

Back 21

Normal force exerted per unit area.

Front 22

Upthrust

Back 22

The force exerted on an object due to the displacement of fluid in which the object is submerged.

Front 23

Principle of flotation

Back 23

A submerged object displaces a weight of fluid equal to its own weight.

Front 24

Centre of gravity

Back 24

The point at which the whole weight of the object seems to act.

Front 25

Moment/Torque

Back 25

The product of the force and the perpendicular distance from the force to the pivot.

Front 26

Couple

Back 26

Two forces that are antiparallel, of equal magnitude, and do not act along the same line of action. They produce only a turning effect.

Hint 26

Do not act along the same line of action!

Front 27

Equilibrium

Back 27

No net moment acting on the body about any point, No net force acting on the body.