Question

the velocity of a particle of a mass 150 g changes from 8 m/s to 12 m/s in two seconds . Assuming that the constant force acts on it find the magnitude of the force

Answer 1

Answer:

Force = Mass × Acceleration.

Acceleration = Change in velocity / time.

a = 12-8/ 2 = 2 m/s

m = 150 g = 0.15 kg.

Since u have to convert all to S.I units or c.gs units.

I am doing it in s.i. units.

Force = 0.15 × 2 kg m/s

Force = 0.3 N..

Answer 2

Given :-

Mass = 150 g

Velocity of particle of mass changing from 8 m/s to 12 m/s = 2 seconds

To Find :-

Assuming that the constant force acts on it find the magnitude of the force.

Solution :-

We know that,

• v = Final velocity
• u = Initial velocity
• a = Acceleration
• t = Time
• m = Mass

Given that,

Mass = 150 g

Time required to change 8 m/s to 12 m/s = 2 second

The mass of the body is given in grams. Converting it to the SI unit kg, we get

$\boxed{\sf Gram \ to \ kilograms= Gram \div 1000}$

Mass = $\sf \dfrac{150}{1000}$

Mass = 0.15 kg

First we have to find the acceleration of the body.

Acceleration of the body is given by the formula,

$\sf Acceleration=\dfrac{(v-u)}{t}$

Where v is the final velocity , u is the initial velocity and t is the time taken.

Substituting the given data we get the value of acceleration.

$\sf Acceleration=\dfrac{(12-8)}{2}$

$\sf Acceleration=\dfrac{4}{2}=2 \: m/s^{2}$

Hence the acceleration of the body is 2 m/s²

Now we need to find the force applied on the body,

By Newton's second law of motion, we know that

$\boxed{\sf Force=Mass \times Acceleration}$

Substitute the value of mass and acceleration,

$\sf Force = 0.15 \times 2$

$\sf F = 0.3\: N$

Hence the force acting on the body is 0.3 N

To Note :-

Velocity defines the direction of the movement of the body or the object.

Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity.