Question

give a simple explaination of newton's second law of motion.....
pls answer fast with no SPAM..!!!​

Answer 1

Answer -

Let us first understand what is momentum -

Definition -

Momentum of a particle is defined as quantity of motion possessed by it and measured by mass of particle and its velocity.

$\rm \vec p = m \vec v$

Description - Suppose a cricket ball is rolling around the ground. Some force will be required to stop it. Again, if a cricket ball and an iron ballof same size are rolled, much greater force will be required to stop it because mass of iron ball is greater than that of cricket ball.

$\implies$Thus, mass and velocity together increases the motion of the body. The product of two quantities, the mass and velocity which measures motion of body is called momentum.

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$\underline{\bf\pink{Newton's\: second\: law \:of\: motion :-}}$

According to it, the rate of change of a body is directly proportional to the applied unbalanced force.

$\boxed{\rm\red{ Rate \:of \:change\: of \:momentum \propto Force\: Applied }}$

It gives the measurment of force.

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Let a body is moving with initial velocity u and after applying a force F on it, its velocity becomes v in time t.

Initial momentum = $\rm p_1 = mu$

Final momentum = $\rm p_2 = mv$

Change in momentum in time t is mv - mu

So rate of change of momentum =

$\rm \frac{mv - mu}{t}$

But according to Newton's second law,

$\implies$$\rm \frac{mv - mu}{t} \propto F$

$\implies$$\rm F \propto \frac{m(v - u)}{t}$

$\implies$$\rm F \propto ma \: \: \: \: \: \: \: [ a = \frac{ v - u }{t} ]$

$\implies$$\rm F = kma$ ( where k is proportionality constant )

$\implies$$\rm F = ma$

So the magnitude of the resultant force acting on a body is equal to the product of mass of body and the acceleration produced.

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Answer 2

Let us first understand what is momentum -

Definition -

Momentum of a particle is defined as quantity of motion possessed by it and measured by mass of particle and its velocity.

\rm \vec p = m \vec v

p

=m

v

Description - Suppose a cricket ball is rolling around the ground. Some force will be required to stop it. Again, if a cricket ball and an iron ballof same size are rolled, much greater force will be required to stop it because mass of iron ball is greater than that of cricket ball.

\implies⟹ Thus, mass and velocity together increases the motion of the body. The product of two quantities, the mass and velocity which measures motion of body is called momentum.

━━━━━━━━━━━━

\underline{\bf\pink{Newton's\: second\: law \:of\: motion :-}}

Newton

′

ssecondlawofmotion:−

According to it, the rate of change of a body is directly proportional to the applied unbalanced force.

\boxed{\rm\red{ Rate \:of \:change\: of \:momentum \propto Force\: Applied }}

Rateofchangeofmomentum∝ForceApplied

It gives the measurment of force.

━━━━━━━━━━━━

Let a body is moving with initial velocity u and after applying a force F on it, its velocity becomes v in time t.

Initial momentum = \rm p_1 = mup

1

=mu

Final momentum = \rm p_2 = mvp

2

=mv

Change in momentum in time t is mv - mu

So rate of change of momentum =

\rm \frac{mv - mu}{t}

t

mv−mu

But according to Newton's second law,

\implies⟹ \rm \frac{mv - mu}{t} \propto F

t

mv−mu

∝F

\implies⟹ \rm F \propto \frac{m(v - u)}{t}F∝

t

m(v−u)

\implies⟹ \rm F \propto ma \: \: \: \: \: \: \: [ a = \frac{ v - u }{t} ]F∝ma[a=

t

v−u

]

\implies⟹ \rm F = kmaF=kma ( where k is proportionality constant )

\implies⟹ \rm F = maF=ma

So the magnitude of the resultant force acting on a body is equal to the product of mass of body and the acceleration produced.