Physical World Units and Measurements - Result Question 47

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48. The percentage errors in the measurement of mass and speed are $2 %$ and $3 %$ respectively. The error in kinetic energy obtained by measuring mass and speed will be [1995]

======= ####48. The percentage errors in the measurement of mass and speed are $2 %$ and $3 %$ respectively. The error in kinetic energy obtained by measuring mass and speed will be [1995]

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/physical-world-units-and-measurements/physical-world-units-and-measurements—result-question-47.md (a) $12 %$

(b) $10 %$

(c) $8 %$

(d) $2 %$

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Answer:

Correct Answer: 48. (c)

Solution:

  1. (c) Percentage error in mass $(\frac{\Delta m}{m} \times 100)=2$ and percentage error in speed $(\frac{\Delta v}{v} \times 100)=3$.

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

$\therefore$ Error in measurement of kinetic energy $\frac{\Delta K}{K}=\frac{\Delta m}{m}+2(\frac{\Delta v}{v})$

$=(\frac{2}{100})+(2 \times \frac{3}{100})=\frac{8}{100}=8 %$

$\therefore %$ age error $=8 %$.