Average speed = distance/time
Average acceleration = change in velocity/time taken.
Gravity = height of the fall x2/ time^2 (g = 2h/t^2).
Resultant force = mass x acceleration (f = ma)
Density = mass/volume
Weight = mass x g (w=mg)
Force = mass x acceleration.
Pressure = force/area
Work done = force x distance moved in the direction of the force.
P.E = mgh (mass x acceleration due to gravity x height)
K.E = ½m x v^2 (½ mass x speed^2)
Stopping distance = thinking distance + braking distance
Efficiency = useful energy output/ total energy input x 100
Power = work done/ time taken or power = energy/time
Useful power output = force x speed (F x v)
Gradient (motion graphs) = distance travelled/ time taken
Hooke’s law =spring constant x extension
Frequency = number of cycles / (per) second (1/s)
Period = 1/frequency (1/f)
Wave speed = frequency x wave length (v = f x λ)
PHYSICS™ -Roshan Rao
Speed of sound = distance travelled / time taken
*echo = x2 distance to wall / echo time
Refractive index = speed of light in a vacuum / speed of light in medium (n=c/v)
Refractive index 2 = sin i/ sin r
Magnification = image height / object height
Angle of incidence = angle of reflection
Linear magnification = image height/object height = image distance/object distance
Kelvin temp = Celsius temp + 273
Energy transferred (specific heat capacity) = mass x specific heat capacity x temp change (E=mc∆T)
Energy = power x time
Specific heat capacity = power x time
Energy transferred (latent heat of fusion) = mass x specific latent heat (E=mL)
Melting point of a substance = freezing point of the substance
Charge = current x time
Resistance = voltage/ current
Resistance in parallel = R1 x R2/ R1 + R2
Resistance in series = R1 + R2
Momentum = mass x velocity
Moment of a force about a point = force x perpendicular distance from point
Pressure in liquids = Pgh (P = Density of liquid) (g = gravity (10 N/Kg)) (h = depth)
Pressure on the base of a liquid filled container = PgAh (A = area of base)