Question

If there is a positive error of $50\%$ in the measurement of velocity of a body, find the error in the measurement of kinetic energy.

Answer 1

Kinetic energy, $E=\frac{1}{2}m{v}^2$

$\therefore \frac{△E}{E}\times 100=(\frac{△m}{m}+\frac{2△v}{v})\times 100$

Here $△m=0$ and $\frac{△v}{v}\times 100=50\%$

$\therefore \frac{△E}{E}\times 100=2\times 50=100\%$