Question 182: Work, Energy and Power & Circular Motion

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

Accepted Answer

The average speed of the athelete
$v = {{100} \over {10}} = 10m/s\,\,\,\,$ $	herefore$ $K.E. = {1 \over 2}m{v^2}$
If mass of athlete is $40$ $kg$ then, $K.E.$ $ = {1 \over 2} 	imes 40 	imes {\left( {10} ight)^2} = 2000J$
If mass of athlete is $100$ $kg$ then, $K.E.$ $ = {1 \over 2} 	imes 100 	imes {\left( {10} ight)^2} = 5000J$
His kinetic energy can be in the range = 2000 J to 5000 J.

Answer

$200J-500J$

Answer

$2 	imes {10^5}J - 3 	imes {10^5}J$

Answer

$20,000J - 50,000J$

Answer

$2,000J - 5,000J$

Work, Energy and Power & Circular Motion

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

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