Question

guys please tell me all physics formula from class 9 cbse NCERT. All Formulas - 50 points and brainest answer

Answer 1

$v \: = u + at$

$2as \: = {v}^{2} - {u}^{2}$

$s \: = ut \: + \frac{1}{2} a {t}^{2}$


$f \: = m \times a$

$ke \: = \frac{1}{2} m {v}^{2}$


$a = \frac{v - u}{t}$

$w \: = m \times g$

Answer 2

Density is mass per unit volume

Density = mass / volume

velocity = displacement / time

Force = rate of change of momentum

Momentum = mass

.

velocity

Power is rate of work done

Power = work / time

Unit of power is watt

Potential energy (P)

PE = m.g.h

m = mass

g = acceleration due to gravity (9.81m/s

2

)

h = height

Kinetic energy (P)

P = (1/2).m.v

2

 

m = mass

v = velocity

Gravity (Force due to gravity)

F

g

: Force of attraction

G : Gravitational constant

M

1

: Mass of first object

M

2

: Mass of second object

Acceleration due to gravity at a depth 'd' from earth surface is :

Acceleration due to gravity at height 'h' from earth surface is :

h is very much smaller than R

Escape velocity

Escape velocity

from

a body of mass M and radius r is

For example if you want to calculate the escape verlocity of sa object from

earth then,

M is dmass of earth

r is radius of earth

OPTICS

 

Index of refraction

 

n = c/v

n - index of refraction

c - velocity of light in a vacuum

v - velocity of light in the given material

Under constant acceleration linear motion

 

v = final velocity

F g = G M 1 M 2

         r 2

 

g d = g(1- d )

R g h = g(1- 2h )

R

         

u = intitial velocity

a = acceleration

t = time taken to reach velocity v from u

s = displacement

v = u + a t

s = ut + (1/2)a t

2

 

s = vt - (1/2)a t

2  v 2 = u 2 + 2 a s

Friction force (kinetic friction)

 

When the object is moving then Friction is defined as :

F

f   = μ F n

 where

F

f   = Friction force, μ= cofficient of friction

 

F n = Normal force

Linear Momentum

 

Momentum = mass x velocity

Capillary action

The height to which the liquid can be lifted is given by:

h = 2γcosθ

ρgr  

 

γ: liquid

-air surface tension(T)(T=energy/area)

θ: contact angle

 

ρ: density of liquid

g: acceleration due to gravity

r: is radius of tube

Simple harmonic motion  

Simple harmonic motion is defined by:

d 2 x/dt 2 = - k x

Time period of pendulum   Waves

f = 1 T ω =  2 π