Equations

Question 1

What is the equation for Weight?

Answer 1

Weight (N) = mass (kg) x gravitational field strength (N/kg)

W = m x g

Question 2

What is the equation for Work done?

Answer 2

Work done (J) = force (N) x distance (m)

W = F x s

Question 3

What is the equation for Force applied to a spring?

Answer 3

Force applied to a spring (N) = spring constant (N/m) x extension (m)

F = k x e

Question 4

What is the equation for distance travelled?

Answer 4

distance travelled (m) = speed (m/s) x time (s)

s = v x t

Question 5

What is the equation for acceleration?

Answer 5

acceleration (m/s^2) = change in velocity / time taken (s)

a = Δv / t

Δv = final velocity - initial velocity

Question 6

What is the equation for Resultant force?

Answer 6

Resultant force (N) = mass (kg) x acceleration (m/s^2)

F = m x a

Question 7

What is the equation for momentum?

Answer 7

momentum (kgm/s) = mass (kg) x velocity (m/s)

p = m x v

Question 8

What is the equation for Kinetic energy?

Answer 8

Kinetic energy (J) = 0.5 x mass (kg) x (velocity)^2 (m/s^2)

Ek = 0.5 x m x v^2

Question 9

What is the equation for gravitational potential energy?

Answer 9

GPE (J) = mass (kg) x gravitational field strength (N/kg) x height (m)

Ep = m x g x h

Question 10

What is the equation for power (energy transferred)?

Answer 10

power (W) = energy transferred / time (s)

P = E / t

Question 11

What is the equation for power (work done)?

Answer 11

power (W) = work done / time (s)

P = W / t

Question 12

What is the equation for efficiency (energy transfer)?

Answer 12

efficiency = useful output energy transfer (J) / total input energy transfer (J)

Question 13

What is the equation for efficiency (power)?

Answer 13

efficiency = useful power output (J) / total power input (J)

Question 14

What is the equation for wave speed?

Answer 14

wave speed (m/s) = frequency (Hz) x wavelength (m)

v = f x λ

Question 15

What is the equation for charge flow?

Answer 15

charge flow (C) = current (A) x time (s)

Q = I x t

Question 16

What is the equation for potential difference?

Answer 16

potential difference (V) = current (A) x resistance (Ω)

V = I x R

Question 17

What is the equation for power (potential difference)?

Answer 17

power (W) = potential differnce (V) x current (A)

P = V x I

Question 18

What is the equation for power (current)?

Answer 18

power (W) = (current)^2 (A) x resistance (Ω)

P = I^2 x R

Question 19

What is the equation for energy transferred (transferred power)?

Answer 19

energy transferred (J) = power (W) x time (s)

E = P x t

Question 20

What is the equation for energy transferred (transferred charge flow)?

Answer 20

energy transferred (J) = charge flow (C) x potential difference (v)

E = Q x V

Question 21

What is the equation for density?

Answer 21

density (Kg/m^3) = mass (kg) / volume (m^3)

ρ = m / V