Forces and Movement

Scalar quantity

Physical quantity that has magnitude (size) only

with no direction

Vector quantity

Physical quantity that has both magnitude (size) and direction

Example of scalars

• Speed

• Distance

• Mass

• Time

• Temperature

• Energy

• Volume

Examples of vectors

• Velocity

• Displacement

• Force

• Acceleration

• Weight

• Momentum

Weight

Force acting on a mass due to the effect of gravitational field

Electric

Attraction or repulsion between 2 charged object

Magnetic

Attraction or repulsion due to magnetic fields

Tension

Occurs within materials/objects when stretched

Compression

Occurs within materials/objects when squashed

Lift

An upwards force generated by the wing of an aircraft when there is a difference in pressure above and below the wing

Thrust

A force which propels an object forward

usually refers to forward force generated by engines

Friction

A force which opposes the motion of an object

Upthrust/Buoyancy

The force which enables objects to float due to the displacement of fluids

Contact

A force which occurs whenever an object rests on something else

and which always acts at 90 degrees to the surface where it rests

Formula Weight

Weight = mass x gravitational field strenght

Units for weight formula

Weight = N

Mass = Kg

Gravitational field strenght = g = 10N/kg

Formula average velocity

average velocity/speed = distance / time

Formula acceleration

Acceleration = Change in speed / time