Physics Equations with Mnemonics

Question 1

Weight

Answer 1

W = m x g

Where’s = mr. g

weight = mass × gravitational field strength (g)

Question 2

Work Done

Answer 2

W = F x s

Widow = Farted Stealthily

work done = force × distance along the line of action of the force

Question 3

Force applied to a spring

Answer 3

F = k x e

Fancy = kissing elvis

force applied to a spring = spring constant × extension

Question 4

Momentum of a force

Answer 4

M = F d

Mmmm! = Flour dumplings

moment of a force = force × distance normal to direction of force

Question 5

Pressure

Answer 5

p = F ÷ A

or

F = A x p

Filthy = Apple pie

pressure = force normal to a surface area of that surface

Question 6

Distance Travelled

Answer 6

s = v x t

Soft = Velvet Trolls

distance travelled = speed × time

Question 7

Acceleration

Answer 7

a = ∆ v ÷ t

or

∆ v = a x t

Change V = at (taxes)

Question 8

Resultant Force

Answer 8

F = m a

Fat = mosquitoes approaching

resultant force = mass × acceleration

Question 9

Momentum

Answer 9

p = m v

Pimp = my vehicle

momentum = mass × velocity

Question 10

Kinetic Energy

Answer 10

E_k = 0.5 m v²

Kinky Einstein = makes half Violent Vampires

kinetic energy = 0.5 × mass × speed2

Question 11

Gravitational Potential Energy

Answer 11

E_p = m x g x h

Pickled Exorcists = Microwaved Golden Hotdogs

gravitational potential energy = mass × gravitational field strength (g) × height

Question 12

Power

(First equation)

Answer 12

P = E ÷ t

Parisian = Exorcists (divides) town

power = energy transferred time

Question 13

Power

(second equation)

Answer 13

P = W ÷ t

Parisian = Exorcists (divides) town

power = energy transferred time

Question 14

Efficiency

Answer 14

• *Eff. = E_out**
• *E_in**

efficiency = useful output energy transfer ÷ total input energy transfer

Question 15

Efficiency

(second equation)

Answer 15

Eff. = P_out

P_in

efficiency = useful power output ÷ total power input

Question 16

wave speed

Answer 16

v = f λ

Very = fat duck

wave speed = frequency × wavelength

Question 17

Charge flow

Answer 17

Q = I t

Remove u from Q = u It

charge flow = current × time

Question 18

Potential Difference

Answer 18

V = I R

Very = Important Rat

potential difference = current × resistance

Volts

Amperes

Ohms

Question 19

Power

(electricity, second equation)

Answer 19

P = I² R

P = I R I (Hot! Hot! Think Nando’s)

power = current 2 × resistance

Question 20

Power

(electricity, first equation)

Answer 20

P = I V

Pointless = Idiots Vanished

power = current x potential difference

Question 21

Energy transferred

(electricity, first equation)

Answer 21

E = P t

Elegant = Pink trousers

energy transferred = power × time

Question 22

+Energy Transferred

(electricity, second equation)

Answer 22

E = Q V

Elephant = Queen Vomits

energy transferred = charge flow × potential difference

Question 23

Density

Answer 23

ρ = m ÷ v

or

m = v x ρ

Rho(ρ) = my (divide) vehicle

density = mass ÷ volume