Q. A body travels uniformly a distance of $(13.8\ \pm 0.2)\ m$ in a time ($4.0 \pm 0.3)\$s. The velocity of the body within error limits is
A) $(3.45 \pm 0.2)\ ms^{- 1}$
B) $(3.45 \pm 0.3)\ ms^{- 1}$
C) $(3.45 \pm 0.4)\ ms^{- 1}$
D) $(3.45 \pm 0.5)\ ms^{- 1}$
Explanation
Here, $S = (13.8 \pm 0.2)m$ and $t = (4.0 \pm 0.3)\ \sec$ Expressing it in percentage error, we have, $S = 13.8 \pm \frac{0.2}{13.8} \times 100\% = 13.8 \pm 1.4\%$ and $t = 4.0 \pm \frac{0.3}{4} \times 100\% = 4 \pm 7.5\%$ $\because V = \frac{s}{t} = \frac{13.8 \pm 1.4}{4 \pm 7.5} = (3.45 \pm 0.3)\ m/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.