Damnnnn lazy to post =x... sucks man physics.. so much of the DAMN formula lol..

n = sin90 / sin c

sin c = 1/n

c : critical angle
n : refractive index of denser medium

refractive index : n = c/v

c : speed of light in vacum
v : speed of light in medium


n= sin i / sin r

i : angle of incidence
r: angle of refraction


f = 1/T
T= 1/F

v=F x lamda

v= wave speed ( in m/s )
f = frequency
lamda = wave length ( in m )


Speed = distance moved / time taken



average speed = total distance moved / time taken


SI unit for speed = m/s or ms-1

velocity = displacement (linear distance) / time taken




Acceleration= v - u / t

u = initial velocity
v = final velocity
t = time taken

SI unit for acceleration is m/s2 or ms-2

Fnet = ma

Fnet : Resultant force
m : mass ( in kg )
a : acceleration (in m/s2)

W= mg

W : Weight
m : mass ( in kg )
g : acceleration due to gravity (10m/s2)


P = m/v

P : Density ( in kg / m2 )
m : mass ( in kg )
v : volume of object ( in m3)

M = f x d

M : Moment
f : force ( in N )
d : perpendicular distance from pivot ( in m )

SI unit = Nm

Using the principle of moment ,
Sum of clockwise moment = Sum of Anti-Clockwise moment


Ek = 1/2 mv2

Ek : Kinetic energy ( in J )
m : mass of object ( in kg )
v : speed of object ( in m/s )

Ep = mgh

Ep : gravitational potential energy
m : mass of object ( in kg )
g : 10N/kg
h : height difference ( in m )

According to the law of conservation of energy ,
Ek = Ep
1/2mv2 = mgh


W = FS

W : Work Done
F : Constant force ( in N )
S : Distance moved in the direction of the force ( in m )

P= E/t = W/t

P : Power ( in W )
E/t = 1/2mv2 or mgh E : Energy converted ( in J )
t : time taken ( in s )

W=F x S

W : work done



SI unit for current = A

I = Q/T

I : current ( in A )
Q : number of coulombs of charge ( in C )
t : time ( in s )


e.m.f = E/Q = W/Q


e.m.f : electromotive force ( in volt , V )
Q : number of coulombs of charge ( in C )
W : work done

V = E/Q

V : potential difference ( p.d )
E/W : energy / workdone
Q : number of coulombs of charge ( In C )

R= V/I

R : resistance ( in ohms )
V : potential difference ( p.d , in V )
I : current flowing throught the material ( in A )


The larger the cross sectional area (thicker) of a wire , the lower is its resistance

The longer the length ( l ) of a wire , the higher the resistance


Wtf so mani formulas.. headache.. all jy for exams ^^