Formulas

Question 1

What is the formula for weight?

Answer 1

Weight (N) = Mass (kg) x Gravitational Field Strength (N/kg)

W = m x g

Question 2

What is the formula for work done?

Answer 2

Work Done (J) = Force (N) x Distance (moved along the line of action of the force) (m)
W = F x s

Question 3

What is formula for hook’s law?

Answer 3

Force (N) = Spring constant (N/m) x Extension (m)

Question 4

How do you calculate a moment?

Answer 4

Moment of a force (Nm) = Force (N) x Distance (perpendicular distance from pivot to lone of action of force) (m)
M = Fd

Question 5

How do you calculate distance (using speed and time)?

Answer 5

Distance travelled (m) = speed (m/s) x time (s)
S = vt

Question 6

How do you calculate acceleration?

Answer 6

Acceleration (m/s^2) = Change in velocity (m/s) ÷ Time (s)
a = v - u ÷ t

v = final velocity 
u = initial velocity

Question 7

Netwon’s Second Law Formula

Answer 7

Resultant Force (N) = Mass (kg) x Acceleration (m/s^2)
F = ma

Question 8

How do you calculate stopping distance?

Answer 8

Stopping Distance = Thinking Distance + Braking Distance

Question 9

How do you calculate a momentum?

Answer 9

Momentum (kg m/s) = Mass (kg) x Velocity (m/s)

P = m x v

Question 10

Gravitational Potential Energy Formula

Answer 10

Gravitational Potential Energy (J) = Mass (kg) × Gravitational Field Strength (N/kg) × Height (m)
E(p) = mgh

Question 11

Kinetic Energy Formula

Answer 11

Kinetic Energy (J) = 1/2 × Mass (kg) × Speed^2 (m/s)
E(k) = 1/2mv^2

Question 12

Elastic Potential Energy Formula

Answer 12

Elastic Potential Energy (J) = 1/2 × Spring Constant (N/m) × Extension (m)
E(e) = 1/2ke^2

Question 13

Calculating Power

Answer 13

Power (W) = Energy Transferred (J) ÷ Time (s)
P = E ÷ t

Power (W) = Work Done (J) ÷ Time (s)
P = W ÷ t

Question 14

Specific Heat Capacity

Answer 14

Change in Thermal Energy (J) = Mass (kg) x Specific Heat Capacity (J/kg°C) x Temperature Change (°C)
ΔE = mcΔθ

Question 15

Efficiency

Answer 15

Efficiency = Total Power Output ÷ Total Power Input

Question 16

How do you calculate wave speed?

Answer 16

Wave Speed (m/s) = Frequency (Hz) x Wavelength (m)
v = fλ

Question 17

Magnification Formula

Answer 17

Image height (new) 
--------------------
Object height (real)

Question 18

Power of Lens Formula

Answer 18

Focal Length

Question 19

Charge Formula

Answer 19

Charge (C) = Current (A) x Time (s)

Q = It

Question 20

Potential Difference Formula

Answer 20

Potential Difference (V) = Current (A) x Resistance (Ω)
V = IR

Question 21

Specific Latent Heat

Answer 21

Energy (J) = Mass (kg) x Specific Latent Heat (J/kg)

E = mL