Question

A moving body mass 20 Kg has 40 J of kinetic energy. Calculate its speed.​

Answer 1

Answer:

Speed or velocity of the body is 2 m/s.

Explanation:

Given :-

Mass = 40 Kg

Kinetic energy = 40 J

To find :-

Speed

Solution :-

Kinetic energy = $\frac{1}{2} * mass * velocity^2$

• $40$ = $\frac{1}{2} * 20 * velocity^2$

• $velocity^2\;=40 * \frac{2}{20}$

• $velocity^2\;=\;\frac{8}{2}$

• $velocity^2\;=\;4$

• $velocity\;=\;\sqrt{4}$

• $velocity\;=\;2$

∴ Speed or velocity of the body is 2 m/s.

Answer 2

Answer:

2 m/s

Explanation:

KE= 1/2mv² (Rearrange the formula)

${v} = \frac{ \sqrt{2ke} }{m}$

v= √2(40) / 20

v= √80/20

v=√4

v= 2

I hope it helps(^.^)