Question

An object of mass 200 g moving with velocity 50 m/ s. What is its kinetic energy?​

Answer 1

given :

$\sf \: m = 200 \: g = 0.2 \: kg \\ \sf \: v = 50 \: m/s$

solution :

$\sf \: K.E = \frac{1}{2} m {v}^{2} \\ \\ \sf \: K.E = \frac{1}{2} \times 0.2 \times {50}^{2} \\ \\ \sf \: K.E = 250 \: j$

Answer 2

Answer:

250 Joules.

Explanation:

$\underline{\bigstar\:\textsf{Given:}}$

• Mass (m) = 200 g
• Velocity (v) = 50 m/s

$\underline{\bigstar\:\textsf{To\:find:}}$

• Kinetic energy (K.E) = ?

$\underline{\bigstar\:\textsf{Solution:}}$

Here, unit of mass is gram but the SI unit of mass is kg so we will convert it.

200 g = 200/1000 = 0.2 kg.

We know, $\green{\sf{Kinetic\:energy\:=\:\dfrac{1}{2}mv^2}}$

Here, m = mass of body

$\:\:\:\:\:\:\:\:$ v = velocity with which the body is moving.

[Just substitute all given values]

$\longmapsto\:\sf{K.E\:=\:\dfrac{1}{2}\:\times\:0.2\:\times\:(50)^2}$

$\:$

$\longmapsto\:\sf{K.E\:=\:\dfrac{1}{\cancel{2}}\:\times\:\dfrac{\cancel{2}}{10}\:\times\:2500}$

$\:$

$\longmapsto\:\sf{K.E\:=\:\cancel{\dfrac{2500}{10}}}$

$\:$

$\small\longmapsto\underline{\boxed{\sf\purple{Kinetic\:energy\:=\:250\:J}}}$