Crucial Equarions To Learn

Question 1

Kinetic energy

Answer 1

Ek = 1/2mv^2

Question 2

Gravitational potential energy

Answer 2

Gpe = mgh

Question 3

Power

Answer 3

Power = work done / time

Power = energy / time

P = IV

P = I^2 x R

Question 4

Efficiency

Answer 4

Useful energy output / total energy input

Question 5

Elastic potential energy

Answer 5

Ep = 1/2ke^2

Question 6

Change in thermal energy

Answer 6

E = Mass X specific heat capacity X temperature change

Question 7

Charge flow

Answer 7

Q = IT

Question 8

Potential Difference

Answer 8

V = IR

Potential difference = Current x Resistance

Question 9

Total resistance

Answer 9

Total resistance = Resistance of component 1 + resistance of component 2

Rt = R1 + R2

Question 10

Energy transferred

Answer 10

Energy transferred = Power x time
(E = Pt)

Energy transferred = Charge flow x Potential difference
(E = QV)

Question 11

Density

Answer 11

Mass / Volume

Question 12

Thermal energy for a change in state

Answer 12

E = mL

Energy = Mass x Specific latent heat

Question 13

Wave speed

Answer 13

Wave speed = Frequency x Wavelength

Question 14

Weight

Answer 14

W = mg

Weight = Mass x Gravitational field strength

Question 15

Work done

Answer 15

W = FD

Work done = Force x Distance (moved along the line of action of the force)

Question 16

Force

Answer 16

F = ke
(Force = Spring constant x Extension)

F = ma
(Force = Mass x Acceleration)

F = mΔv / t
(force = change in momentum / time)

F = M / D
(Force = moments / distance)

Question 17

Momentum

Answer 17

Momentum = Mass x Velocity

p = mv

Question 18

Pressure

Answer 18

P = hρg
(pressure = Height x Density of liquid x gravitational field strength)

Question 19

Change in velocity

Answer 19

v^2 - u^2 = 2as

(final velocity)^2 - (initial velocity)^2 = 2 x acceleration x DISTANCE