Formulae

Question 1

Formula for Speed

Answer 1

v = s/t

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

Question 2

Formula for Acceleration

Answer 2

a = Δv/Δt

a = acceleration (m/s²)
Δv = Δ velocity (m/s)
Δt = Δ time (s)

Question 3

Formula for force

Answer 3

F = ma

F = Force (N)
m = mass (kg)
a = acceleration (m/s²)

Question 4

Formula for Density

Answer 4

ρ = m/v

ρ = density (g/ml or g/cm³)
m = mass (g)
v = volume (ml or cm³)

Question 5

Formula for Acceleration due to Gravity

Answer 5

F_g = mg
Fg = Force due to gravity (N)
m = mass (kg)
g = acceleration due to gravity (m/s²) (9.8m/s²)

Question 6

Formula for Pressure

Answer 6

P = F/A
P = Pressure (Pa)
F = Force (N)
A = Area (m²)

Question 7

Formula for Pressure in Liquids

Answer 7

P = ρgΔh
ρ = Density of liquid (Pa)
g = Gravitational field strength (9.8m/s²)
Δh = Change in depth (m)

Question 8

Formula for Spring constant

Answer 8

k = F/x

k = spring constant (N/m)
F = force (N)
x = extension (m)

Question 9

Formula for Moments

Answer 9

τ = Fd

τ = moments (Nm)
F = force (N)
d = perpendicular distance from pivot (m)

Question 10

Formula for Momentum

Answer 10

ρ = mv

ρ = momentum (kgm/s)
m = mass (kg)
v = velocity(m/s)

Question 11

Formula for Impulse

Answer 11

Δρ = FΔt

Δρ = impulse (kgm/s or Ns)
F = force (N)
Δt = change in time (s)

Question 12

Formula for Kinetic energy

Answer 12

E_k = ¹/₂mv²

E_{k</sub = kinetic energy (J)
m = mass (kg)
v = speed (m/s)}

Question 13

Formula for Gravitational Potential

Answer 13

E_p = mgΔh

E_p = gravitational potential (J)
m = mass (kg)
g = gravitational field strength (9.8m/s²)
Δh = change in height (m)

Question 14

Formulae for Power

Answer 14

P = w/t or P = ΔE/t

P = power (W)
t = time (s)
w = work (J)
ΔE = change in energy (J)

Question 15

Formula for Efficiency

Answer 15

Efficiency (%) = (Useful energy/Total energy) x 100

Question 16

Formula for Work

Answer 16

W = Fd

W = work (J)
F = Force (N)
d = Distance (m)

Question 17

Wave equation

Answer 17

v = fλ

v = Wave speed (m/s)
f = frequency (Hz)
λ = Wavelength (m)

Question 18

Formula to for the refractive index

Answer 18

n = sinϴ_I/sinϴ_R

n = Refractive index
ϴ_I = Angle of incidence
ϴ_R = Angle of refraction

Question 19

Formula for the refractive index concerning the speed of light

Answer 19

n = c/v

n = Refractive Index
c = Speed of light (3x10⁸m/s)
v = Current velocity of wave (m/s)

Question 20

Formula for the refractive index of a substance using the critical angle

Answer 20

n = 1/sin(ϴ_c)

ϴ_c = Critical angle

Question 21

Formula for Current

Answer 21

I = Q/t

I = Current (A)
Q = Charge (C)
t = Time (s)

Question 22

Formula for E.M.F

Answer 22

E = W/Q

E = E.M.F (V)
W = Work (J)
Q = Charge (C)

Question 23

Formula for Potential Difference

Answer 23

V = W/Q

V = Potential difference (V)
W = Work (J)
Q = Charge (C)

Question 24

Ohms’s Law

Answer 24

V = IR

V = Voltage (V)
I = Current (A)
R = Resistance (Ω)

Question 25

Formula for the total resistance in a series circuit

Answer 25

R_T = R₁ + R₂ + R₃…

R = Resistance (Ω)

Question 26

Formula for the total resistance in a parallel circuit?

Answer 26

1/R_T = 1/R₁ + 1/R₂ + 1/R₃…

R = Resistance (Ω)

Question 27

Formula for Electrical Power

Answer 27

P = IV

P = Power (W)
I = Current (A)
V = Voltage (V)

Question 28

Two formulas derived from V = IR and P = IV

Answer 28

P = I²R

and

P = V²/R

P = Power (W)
I = Current (A)
V = Voltage (V)
R = Resistance (Ω)

Question 29

Formula for Energy (used) in electrical circuits

Answer 29

E = IVt

P = Power (W)
I = Current (A)
V = Voltage (V)
t = Time (s)

Question 30

Formula that shows the relation between Voltage and Number of Coils in a transformer

Answer 30

V_p/V_s = N_p/N_s

V_p = Voltage in Primary Coil (V)
V_s = Voltage in Secondary Coil (V)
N_p = Number of turns in Primary Coil (A)
N_s = Number of turns in Secondary Coil (A)

Question 31

Formula that shows the relation between Voltage and current in a 100% efficient transformer

Does not work if the transformer is not 100% efficient

Answer 31

V_pI_p = V_sI_s

V_p = Voltage in Primary Coil (V)
V_s = Voltage in Secondary Coil (V)
I_p = Current in Primary Coil (A)
I_s = Current in Secondary Coil (A)

Question 32

Formula for the relationship between pressure and volume

Answer 32

pV = constant

p = Pressure (Pa)
V = Volume (m³)

Question 33

Formula for Specific Heat Capacity?

Answer 33

C = ΔE/(mΔT)

C = Specific Heat Capacity(J/(kgK) or Jkg^-1K^-1)
ΔE = Change in Energy (J)
m = Mass (kg)
ΔT = Change in Temperature (K)

Question 34

Formula for the orbital speed of a planet

Answer 34

v = 2πr/T

v = Orbital speed (m/s)
r = Radius of the orbit (m)
T = Time taken for an orbit (s)