Question

An athlete in the Olympic games covers a distance of $100$m in $10$s. His kinetic energy can be estimated to be in the range. (Assume weight = 60kg)

• A. $200J-500J$
• B. $2\times {10}^{5}J-3\times {10}^{5}J$
• C. $20000J-50000J$
• D. $2000J-5000J$

Answer 1

The correct option is D $2000J-5000J$

Velocity $V=\frac{distance}{time}=\frac{100}{10}=10m/s$

Assuming his mass to be 60kg, his kinetic energy is

$K.E=\frac{1}{2}m{v}^2$

$=\frac{1}{2}\times 60\times 100$

$=60\times 50$

$=3000J$

Hence, Option D