Question

A force of 120N acts an a stationaly body for 4 seconds and the body acquires a velocity of 36 ms^1 . Calculate the mass of the body ,​

Answer 1

Required Solution:

Given:

• Force acted (F) = 120 N

• Inital velocity of the body (u) = 0 m/s

[ As it is on stationary position.]

• Final velocity (v) = 36 m/s

• Time (t) = 4 seconds

To calculate:

• Mass of the body (m)

Formula used :

★ $\boxed {\sf{ a = \dfrac{v-u}{t} }}$

★ $\boxed {\sf{ F = ma}}$

Where,

◆ a = acceleration

◆ v = final velocity

◆ u = Inital velocity

◆ m = mass

◆ F = force

Calculation:

We know that,

★ $\boxed {\sf{ F = ma}}$

Let us calculate the acceleration first,

→ We also know that,

★ $\boxed {\sf{ a = \dfrac{v-u}{t} }}$

Inserting values:

$\sf {\longrightarrow a = \dfrac{36-0}{4} \: m/{s}^{2}}$

$\sf {\longrightarrow a = \dfrac{36}{4} \: m/{s}^{2}}$

$\sf \red {\longrightarrow a = 9 \: m/{s}^{2}}$

Now, substituting the value of acceleration in the following formula:

★ $\boxed {\sf{ F = ma}}$

→ 120 = m × 9

→ 120 = 9m

→ m = 120/9

→ m = 13.33 kg

Therefore, mass of the body is 13.33kg.