03. Physics Equations

Question 1

Weight

W

Answer 1

Weight = mass x gravitational field strength

W = m x g

Question 2

Work done

W

Answer 2

Work Done = force x distance (along line of action)

W = F x s

Question 3

Force applied to a spring

F

Answer 3

Force applied to a spring = spring constant x extension

F = k x e

Question 4

(Physics Only) Moment of a force

Answer 4

Moment = force x distance

M = F x d

Question 5

(Physics Only) Pressure

P

Answer 5

Pressure = force normal to a surface / area of that surface

P = F / A

Question 6

Distance travelled

s

Answer 6

Distance = speed x time

s = v x t

Question 7

Force

F

Answer 7

Force = mass x acceleration

F = m x a

Question 8

Acceleration

a

Answer 8

Acceleration = change in velocity / time taken

a = Δv / t

Question 9

Momentum

p

Answer 9

Momentum = mass x velocity

p = m x v

Question 10

Kinetic energy

E_k

Answer 10

Kinetic Energy = 1/2 x mass x (velocity)²

E_k = 1/2 x m x v²

Question 11

Gravitational potential energy

E_p

Answer 11

Gravitational Potential Energy = mass x gravitational field strength x height

E_p = m x g x h

Question 12

Power

P

Answer 12

Power = energy transferred / time

P = E / t

Question 13

Power

P

Answer 13

Power = work done / time

P = W / t

Question 14

Power

P

Answer 14

Power = potential difference x current

P = I x V

Question 15

Power

P

Answer 15

Power = current² x resistance

P = I² x R

Question 16

Efficiency (Energy)

Answer 16

= Useful output energy transfer / total input energy transfer

Question 17

Efficiency (power)

Answer 17

= useful power output / total power input

Question 18

Wave speed

v

Answer 18

Wavespeed = Frequency x wavelength

v = f x λ

Question 19

Charge flow

Q

Answer 19

Charge flow = current x time

Q = I x t

Question 20

Potential difference

V

Answer 20

Potential Difference = current x resistance

V = I x R

Question 21

Energy transferred

E

Answer 21

Energy = power x time

E = p x t

Question 22

Energy transferred

E

Answer 22

Energy transferred = charge flow x potential difference

E = Q x V

Question 23

Density

ρ

Answer 23

Density = mass / volume

ρ = m / V