Scalar: magnitude e.g. mass, energy, speed, distance.

Vector: magnitude and direction e.g. force, velocity, displacement.

F=ma

W=mg

Force (N), m: mass (kg), a: acceleration (m/s^{2}). W: weight (N), g: 9.8 m/s^{2})

Weight is force due to gravity, so can be different on the moon.

Mass doesn't change but g and weight can.

Resultant force: the sum of all forces acting on an object.

Newton’s 1st Law: if there is a resultant force, an object will accelerate or decelerate. If not, the object will remain stationary or at constant speed.

Newton’s 2nd Law: F=ma

Newton’s 3rd Law: when two objects interact, they exert an equal and opposite force on each other.

Terminal velocity: first, the car would accelerate because the driving force is bigger than the resisting force. Then, the resisting force increases. Eventually, driving force = resistance, so the car will continue at a constant speed.

W=Fs

W: work done (J), s: displacement (m).

F=ke

F: Force (N), k: spring constant (N/m), e: extension (m)

Hooke's Law: extension is directly proportional to the force applied, until the limit of proportionality.

Elastic potential energy: equation given.

M=Fd

M: Moment (Nm), d: distance (m).

Moments are the turning effect of a force.

Displacement is distance travelled in a given direction.