Question

A body of mass 6KG puts in rest. How much force exerts on it so that velocity of 4m/s produces in it in 4
seconds ​

Answer 1

Given :

• Mass of a body, m = 6 kg
• Initial velocity, u = 0 m/s
• Final velocity, v = 4 m/s
• Time, t = 4 seconds

To find :

• Force exerted, F

According to the question,

➞ v = u + at [First equation of motion]

Where,

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

➞ Substituting the values,

➞ 4 = 0 + a × 4

➞ 4 - 0 = 4a

➞ 4 = 4a

➞ 4 ÷ 4 = a

➞ 1 = a

• So,the acceleration is 1 m/s².

Now,

➞ Force = Mass × Acceleration

Or,

➞ F = ma

➞ F = 6 × 1

➞ F = 6 N

• So,the force exerted is 6 Newton.

Answer 2

Answer:

Given :-

• Mass = 6 kg
• Initial velocity = 0 m/s
• Time taken = 4 sec
• Final velocity = 4 m/s

To Find :-

Force exerted

Solution :-

Firstly let's find acceleration by using first equation

$\tt \: v = u + at$

Here,

V is the Final Velocity

U is the Initial Velocity

A is the Acceleration

T is the Time

$\sf \: 4 = 0 + a(4)$

$\sf \: 4 = 0 + 4a$

$\sf \: 4 = 4a$

$\sf \: a \: = \dfrac{4}{4}$

$\sf \: a \: = 1$

Acceleration is 1 m/s.

Now,

Let's find Force applied

As we know that

$\tt \: F = ma$

$\sf \: F = 6 \times 1$

$\sf \: F = 6 \: N$