Question

Calculate the amount of kinetic energy a 50 kg runner has when he is going 2 m/s.

Answer 1

Answer:

Given,

mass(m)=50kg

velocity(v)=2m/s

kinetic energy(K.E.)=?

We know that K.E.=1/2mv2

KE=1/2×50×2^2

Explanation:

=1/2×200

=100 Joule

Answer 2

Given:

Mass of the runner (m) = 50 kg

Speed of the runner (v) = 2 m/s

Equation:

$\rm KE = \dfrac{1}{2} mv^2$

Answer:

By substituting values in the equation, we get:

$\rm KE = \dfrac{1}{2} \times 50 \times 2^2 \\ \\ \rm = \dfrac{1}{2} \times 50 \times 4 \\ \\ \rm = 25 \times 4 \\ \\ \rm = 100 \: J$

$\therefore$ Kinetic energy of the runner = 100 J