Physics equations to learn

Equations you must recall (22)

1. distance travelled = average speed × time
2. acceleration = change in velocity ÷ time taken a = (v − u) ÷ t
3. force = mass × acceleration F = m × a
4. weight = mass × gravitational field strength W = m × g
5. momentum = mass × velocity p = m × v
6. change in gravitational potential energy = mass × gravitational field strength × change in vertical height ΔGPE = m × g × Δh
7. kinetic energy = ½ × mass × (speed)² KE = ½ × m × v²
8. efficiency = (useful energy transferred by the device) ÷ (total energy supplied to the device)
9. wave speed = frequency × wavelength v = f × λ
10. wave speed = distance ÷ time v = x ÷ t
11. work done = force × distance moved in the direction of the force E = F × d
12. power = work done ÷ time taken P = E ÷ t
13. moment of a force = force × distance normal to the direction of the force Physics only
14. energy transferred = charge moved × potential difference E = Q × V
15. charge = current × time Q = I × t
16. potential difference = current × resistance V = I × R
17. power = energy transferred ÷ time taken P = E ÷ t
18. electrical power = current × potential difference P = I × V
19. electrical power = current squared × resistance P = I² × R
20. density = mass ÷ volume ρ = m ÷ V
21. force exerted on a spring = spring constant × extension F = k × x
22. pressure = force normal to surface ÷ area of surface P = F ÷ A Physics only

Equations given in the exam (11)

You need to know how to use these, but you do not have to remember them.

1. (final velocity)² − (initial velocity)² = 2 × acceleration × distance v² − u² = 2 × a × x
2. force = change in momentum ÷ time F = (mv − mu) ÷ t
3. energy transferred = current × potential difference × time E = I × V × t
4. force on a conductor at right angles to a magnetic field carrying a current = magnetic flux density × current × length F = B × I × l
5. potential difference across secondary coil ÷ potential difference across primary coil = number of turns in secondary coil ÷ number of turns in primary coil Vs ÷ Vp = Ns ÷ Np Physics only
6. For transformers with 100% efficiency, potential difference across primary coil × current in primary coil = potential difference across secondary coil × current in secondary coil Vp × Ip = Vs × Is
7. change in thermal energy = mass × specific heat capacity × change in temperature ΔQ = m × c × Δθ
8. thermal energy for a change of state = mass × specific latent heat Q = m × L
9. to calculate pressure or volume for gases of fixed mass at constant temperature P1 × V1 = P2 × V2 Physics only
10. energy transferred in stretching = 0.5 × spring constant × (extension)² E = ½ × k × x²
11. pressure due to a column of liquid = height of column × density of liquid × gravitational field strength P = h × ρ × g Physics only