Paper 2 equations Flashcards
Work done =
Force x distance moved in the direction of the force
E = F x d
Power =
(in terms of energy)
rate of energy transferred
or
energy transferred/time taken
P = E/t
charge =
current x time
Q = I x t
potential difference =
(hint: Ohm’s law!)
current x resistance
V = I x R
electrical power =
current x potential difference
P = I x V
or current squared x resistance
P = I^2 R
density =
mass/volume
ρ = m/V
force exerted on a spring =
spring constant x extension
F = k x
TRIPLE ONLY (But you know it from year 9)
Pressure =
Force/area
P = F/A
Energy transferred in a circuit has an equation that sounds like a TV channel - do you remember what it is?
E = I t V
Energy = current x voltage x time
Referring to the equation F = B x I x L Explain the effect on the force of increasing the current passing through a wire that is placed within a magnetic field.
If I is increased, the force will increase.
For transformers with 100% efficiency we can use the equation Vp x Ip = Vs x Is.
What does Vp x Ip tell you about the primary coil?
P = I x V
so you are calculating the power across the primary coil if you do Vp x Ip
In the equation ΔQ = mcΔθ what do the letters stand for?
Δ = change in (Greek letter delta)
Q = energy
m = mass
c = specific heat capacity
Δθ = change in temperature
In the equation Q = mL what do the letters stand for?
Q = energy
m = mass
L = specific latent heat
In the equation E = 1/2 k x^2 for the energy transferred in stretching a spring, what is k called and what property of a spring does it represent?
k is the spring constant and represents stiffness of a spring
