Equations I Need To Know

Question 1

What is the formula for density?

Answer 1

density (kg/m3) = mass (kg)/volume (m3)

ρ = m/V

Question 2

What is the formula for distance ?

Answer 2

distance travelled (m) = speed (m/s) × time(s) 
s = v/t

Question 3

What is the formula for acceleration?

Answer 3

acceleration (m/s2) = change in velocity (m/s)/time(s)

a = (v-u)/t

Question 4

What is the formula for kinetic energy?

Answer 4

kinetic energy (J) = 0.5 × mass (kg) × (speed (m/s))^2
KE = 1⁄2 mv2

Question 5

What is the formula for force?

Answer 5

force (N) = mass (kg) × acceleration (m/s2)

F = ma

Question 6

What is the formula for work done?

Answer 6

work done (J) = force (N) × distance (m) 
WD = F x D

Question 7

What is the formula for power?

Answer 7

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

P = WD / t

Question 8

What is the formula for momentum?

Answer 8

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

p = mv

Question 9

What is the formula for pressure?

Answer 9

Pressure (Pa) = Force (N) / Area (m2)

Question 10

What is the formula for weight?

Answer 10

weight = gravity force (N) = mass (kg) × gravitational field strength, g (N/kg) 
F = W = mg

Question 11

What is the formula for charge flow?

Answer 11

charge flow (C) = current (A) × time (s) 
Q = It

Question 12

What is the formula for potential difference?

Answer 12

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

Question 13

What is the formula for energy transferred?

Answer 13

energy transferred (J) = charge (C) × potential difference (V) 
E = QV

Question 14

What is the formula for energy transferred ?

Answer 14

energy transferred (J, kWh) = power (W, kW) × time (s, h) 
E = Pt

Question 15

What is the formula for wave speed?

Answer 15

wave speed (m/s) = frequency (Hz) × wavelength (m) 
v = fλ

Question 16

What is the formula for efficiency?

Answer 16

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

Question 17

What is the formula for stopping distance?

Answer 17

Stopping distance (m) = thinking distance (m) + braking distance (m)