MCQ
The percentage error in measurement of mass and speed are $3\%$ and $2\%$ then error in kinetic energy will be .......... $\%$
- A$6$
- ✓$7$
- C$10$
- D$12$
✓
Answer
Correct option: B.
$7$
b
$E = \frac{1}{2}m{v^2}$
$E = \frac{1}{2}m{v^2}$
$\%%$ Error in $K.E$. $= \%$ error in mass $+ 2 × \%$ error in velocity $= 3 + 2 \times 2 = 7 \%$
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