Physics Equations Memorize!!!!

Vector Quantities

Displacement, velocity, acceleration, force, torque, momentum, electric field, weight

Scalar quantities

Distance, speed, work/energy, power, pressure, electric potential, temperature, density, mass

Cos 30

√3/2

Cos 45

√2/2

Cos 60

1/2

Cos 90

0

Sin 30

1/2

Sin 45

√2/2

Sin 60

√3/2

Sin 90

1

Three kinematics formuals

d = vi*t + ½ (a)(t²)

vf² = vi² + 2ad

vf = vi +at

X component

Cos theta

Y component

Sin theta

Momentum

p = mv

• m = mass

• v = velocity

Impulse

FΔt = Δp

Work energy therome

W = KE, W = F d = Fdcosθ

Power

Energy/time

Efficiency

W out / E in

Centripetal acceleration

ac = v²/ r

Torque

Torque = rFsintheta

Period

T = 2π/ ω

w = angular velocity

Moment of Inertia

I = mr²

• mass of rotating bodies (kg)

• r = distance of object from centre of axis of rotation (m)

Newtons law of universal gravitation force

Fg = (G m *m )/ r²

Hooke’s law

Fx = -kx

Spring potential energy

U = ½ kx²

Period of a simple harmonic oscillator

Ts = 2pi√m/k

Frequency of a simple harmonic oscillator

f = 1/2pi √k/m

Angular frequency

w = 2pi/T = √k/m

Period of a simple pendulum

Tp = 2pi √L/g

wavelength

= v/f

Intensity of sound

dB = 10log10 (I1/I0)

frequency of string/pipe attached at both ends

f = nv/2L

frequency of pipe open at one end

f = nv/4L

Conservation of flow/equation of continunity

A1v1 = A2v2

Work done by gas

W = PV

• P = pressure

Change in internal energy

U = Q + W

Avg. kinentic energy of molecules of a gas

Kavg = 3/2 KbT = 3R/2N * T

Electric potential energy

U = q V

• q = charge

• V = change in electric potential

Electric potential

V = kQ/ r

Capacitance

C = k Eo A/d

Voltage

I = V/R

Power/Energy dissipation

P = IV

P = I² R

P = V² / R

Current

I = Q/t

Resistance

R = pl/A

• p = resistivity

• l = length

Charge of capacitor

V = Q/C

Uc = ½ QV

Energy of capacitor

Uc = ½ C(V²)

Uc = ½ Q² / C

Index of refraction

n = c/v

Thin lens equation

1/f = 1/do + 1/di

Magnification

M = hi/ho = -di/do

Lens power

P = 1/f

Converging

Convex lens + concave mirror

Diverging

Concave lens + convex mirror

For a converging lens if d0 > 2f

It is smaller, inverted, real

For a converging lens if d0 = 2f

Same size, inverted and real.

For a converging lens, if d0 = f

No image

For converging lens, if d0 < f

Larger, upright, and virtual.

Diverging lens are always

SUV, small, upright, and virtual.

Location conventions

• Lens: real is behind, and virtual is in front

• Mirror: real is in front and virtual is behind.

Sign conventions

• di = + if real image

• di = - if virtual image

• if converging, f = +

• if diverging, f = -

• if magnification positive, it is upright

• if magnification negative, it is inverted.

If the object is between focal point, and 2F

Then it is larger, inverted, and real.

Change in internal energy sign conventions:

• When the gas does work: W < 0

• When the work is done on the gas: W > 0

• When the gas absorbs heat: Q > 0

• When the gas releases heat: Q < 0

Linear thermal expansion

L = aLo T

Light and mediums and n and bending

• If light is moving into a medium with lower n then the light will travel faster and it will bend away from the normal.

• If light is moving into a medium with higher n then the light will travel slower and will bend towards the normal.

Isobaric pressure

Pressure remains constant

Adibatic process

No heat transfer

Isochoric process

Volume remains constant

Isothermal process

Change in internal energy is 0