Question

How fast should a man of mass 60 kg Run so that his kinetic energy is 750 Joule?

Answer 1

Answer:

5m/s

Kinetic energy of man is 1/2mv^2. mass of man is 60kg. Kinetic energy is 750j. so 1/260.v^2=750 so v^2=25 v=5

Answer 2

$\large\sf\underline{Understand\:Concept}$

As per given in the information,mass of a man is 60kg and his kinetic energy is also given 750 J and we have to find velocity so first of all we have to know about the formula of kinetic energy is 1/2 is multiple of mass is mutliple of velocity square.So now let's put the formulae and find the answer!

$\large\sf\underline{Given}$

•A man has a mass of 60 kg.

•Kinetic energy of man is 750 Joule.

$\large\sf\underline{To\:Find}$

•Velocity of a man is = ?

$\large\sf\underline{Solution}$

Given that,

• Mass = 60kg
• Kinetic Energy = 750 Joule
• Velocity = ?

As we know,

$\: \: \sf \:kinetic \: energy = \frac{1}{2} m {v}^{2}$

Now put the value given here

$\: \: \sf \implies \: 750= \frac{1}{2} \times 60 \times {v}^{2} \\ \\ \: \: \sf \implies \: {v}^{2} = \frac{2 \times 750}{60} = 25 \\ \\ \: \: \sf \implies \: v = \sqrt{25} \\ \\ \: \: \sf \implies \: v = 5 \frac{m}{s}$

Hence,Velocity of a man is 5 m/s.

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