Equations Flashcards
Current, charge, time
Charge = current x time Coulombs = amps x seconds Q = Ixt
Current, resistance, voltage
Voltage = current x resistance Volts = amps x ohms V = IxR
Current, power, voltage
Power = current x voltage Watts = amps x volts P = IxV
Current, voltage, Electrical transferred, time
Energy transferred = current x voltage x time
J = amps x volts x seconds
E = IxtxV
Volts squared, power, resistance
Power = voltage squared/Resistance Watts = volts/ohms P = v2/R
Power lost
Power = current squared x resistance Watts = amps x ohms P = I2xR
Time, Energy, power *
Energy = power x time Joules = Watts x seconds E = Pxt
Time, resistance, current squared, energy *
Energy = current squared x resistance x time E = I2xRxt
Mass, acceleration, force
Force = mass x acceleration F = m x a N = kg x m/s2
Mass, weight, gravity
Weight = mass x gravity W = m x g N = kg x N/kg
Mass, gravity, GPE, height
GPE = mass x gravity x height GPE = mgh J = kg x m/s2 x m
1/2, mass, kinetic energy, speed squared
Kinetic energy = 1/2 x mass x speed2
KE = 1/2 x m x v2
J = 1/2 x kg x m/s2
Force, work, distance
Work = force x distance W = f x d J = N x m
Time taken, work done, power
Power = work done/time W = p x t J = W x s
Mass, velocity, momentum
Momentum = mass x velocity P = m x v Kgm/s = kg x m/s
Orbital speed
Orbital speed = 2 x pie x orbital radius/ time
V = 2 x pie x r/ t
m/s
Extension, force applied, spring constant
Force applied = spring constant (stiffness) x extension
F = K x X
N = N/m x m
refractive index
n = sin i/sin r
critical angle
sin c = 1/refractive index (n)
Boyles law
p1V1 = p2V2
Pressure law
p1/t1 = p2/t2 (temperature in kelvin)
Distance speed time
Speed =distance/time
Acceleration equation
A= V-u/t
Equation to find moment
Moment = force x perpendicular distance
M=Fxd
Nm = N x m
Equation for wave speed
Wave speed = frequency x wave length
V = f x delta
m/s = Hz x m
Equation to find time period
Time period = 1/frequency
Equation for efficiency
Efficiency = useful energy/ total energy
Equation linking power, work done and time
Work = power x time
Equation to work out density
Density = mass/volume
p = m/v
Kg/m3 = kg/m3
Equation for area, pressure, force
Pressure = force/area
N/m2
Equation including height density pressure and gravity
Pressure = height x density x gravity
Pa = mx kg m3 x N/kg
Equation for transformers
Input voltage/output voltage = Number of turns on primary coil/Number of turns on secondary coil
What does input voltage x input current equal
Output voltage x output current
Changes in momentum
Force = change in momentum/time
