P1- Equations

Question 1

Work done? (Energy transferred)

Answer 1

W=Fs
Work done (J - joules) = Force (N- newtons) x distance (m - metres)

Question 2

Weight?

Answer 2

W=mg
Weight (N - newtons) = mass (kg - kilograms) x gravitational field strength (N/kg 9.8 on Earth)

Question 3

Gravitational potential energy?

Answer 3

E = mgh
Energy (J - joules = mass (kg) x gravitational field strength (N/kg - 9.8 on Earth) x height (m)

Question 4

Kinetic energy?

Answer 4

E = 1/2 x m x v squared
Energy (J - joules) = 0.5 x mass (kg) x velocity squared (m/s - metres per second)

Question 5

Elastic potential energy?

Answer 5

E = 1/2 x k x e squared
Energy (J - joules) = 0.5 x spring constant (N/m - newtons per metre) x extension squared (m)

Question 6

Efficiency?

Answer 6

Efficiency = useful output/total input

Question 7

Power?

Answer 7

P = E/t
Power (W - Watts) = Energy (J - joules)/ time (second)