Question

A body is moving with uniform acceleration has a velocity 20 m/s. After travelling for 50 sec, its velocity became 40 m/s. Calculate the displacement covered by it during this time.​

Answer 1

Given :

Initial velocity = 20 m/s

Final velocity = 40 m/s

Time interval = 50 s

To Find :

Displacement covered by body in the given interval of time.

Solution :

First of all we have to find acceleration of the body.

• Acceleration is defined as the rate of change of velocity.

Mathematically,

$:\implies\:\underline{\boxed{\bf{\orange{a=\dfrac{v-u}{t}}}}}$

⟩ v denotes final velocity

⟩ u denotes initial velocity

⟩ a denotes acceleration

⟩ t denotes time

By substituting the given values;

$\sf\dashrightarrow\:a=\dfrac{40-20}{50}$

$\sf\dashrightarrow\:a=\dfrac{20}{50}$

$\bf\dashrightarrow\:\underline{\underline{a=0.4\:ms^{-2}}}$

Displacement covered by the body can be calculated by using third equation of kinematics.

$\sf\dashrightarrow\:v^2=u^2+2as$

$\sf\dashrightarrow\:(40)^2=(20)^2+2(0.4)s$

$\sf\dashrightarrow\:1600-400=0.8s$

$\sf\dashrightarrow\:s=\dfrac{1200}{0.8}$

$\dashrightarrow\:\underline{\boxed{\bf{\purple{s=1500\:m}}}}$