Equations to know

Question 1

How do you work out:
Weight
(W=mg)

Answer 1

Weight= mass x gravitational field strength

Question 2

How do you work out:
Force applied to a spring
(K=ke)

Answer 2

Force applied to a string= spring constant x extention

Question 3

How do you work out: Acceleration

a=▪️v/t

Answer 3

Acceleration= change in velocity / time taken

Divide

Question 4

How do you work out:
Momentum
(p=mv)

Answer 4

Momentum= mass x velocity

Question 5

How do you work out:
Gravitational potential energy (GPE)
(Ep=mgh)

Answer 5

GPE= mass x gravitational field strength x height

Question 6

How do you work out:
Power
(P=W/h)

Answer 6

Power= work done / time

Question 7

How do you work out:
Efficiency
(Hint: Power)

Answer 7

Efficiency= useful out / total out (power)

Question 8

How do you work out:
Charge flow
(Q=I t)

Answer 8

Charge flow= current x time

Question 9

How do you work out:
Power
(P=VI)

Answer 9

Power= potential difference x current

Question 10

How do you work out:
Energy transfer
(E=Pt)

Answer 10

Energy transfer= power x time

Question 11

How do you work out:
Density
(p=m/V)

Answer 11

Density= mass/volume

Question 12

How do you work out:
Work done
(W=Fs)

Answer 12

Work done= force x distance(along line of action of the force)

Question 13

How do you work out:
Distance travelled 
(s=vt)

Answer 13

Distance traveled= speed x time

Question 14

How do you work out:
Resultant force
(F=ma)

Answer 14

Resultant force= mass x acceleration

Question 15

How do you work out:
Kinetic energy
(Ek= 0.5mv(squared))

Answer 15

Kinetic energy= 0.5 x mass x (speed(squared))

Question 16

How do you work out: Power

P=E/t

Answer 16

Power= energy transferred / time

Question 17

How do you work out:
Wave speed
(v=f(upside down y))

Answer 17

Wave speed= frequency x wavelength

Question 18

How do you work out:
Potential difference 
(V=IR)

Answer 18

Potential difference= current x resistance

Question 19

How do you work out:
Efficiency
(Energy transfer)

Answer 19

Efficiency= useful output energy transfer/useful input energy transfer

Question 20

How do you work out:
Power
(P=I(squared) R)

Answer 20

Power= current(squared) x resistance

Question 21

How do you work out:
Energy transferred
(E= QV)

Answer 21

Energy transferred= charge flow x potential difference

Question 22

How do you work out:
Pressure
(p= F/A)

Answer 22

Pressure= force to normal surface/area of surface

Question 23

How do you work out:
Momentum of force
(M=Fd)

Answer 23

Momentum of force= force x distance(normal to direction of force)