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Physics · PYQ NEET UG 2023
हिन्दीA metal wire has mass \( (0.4 \pm 0.002)\text{ g} \), radius \( (0.3 \pm 0.001)\text{ mm} \) and length \( (5 \pm 0.02)\text{ cm} \). The maximum possible percentage error in the measurement of density will nearly be:
Correct answer · Option 4
1.6%
Explanation
Density \( \rho = \frac{m}{\pi r^2 l} \). Maximum fractional error \( \frac{\Delta \rho}{\rho} = \frac{\Delta m}{m} + 2\frac{\Delta r}{r} + \frac{\Delta l}{l} = \frac{0.002}{0.4} + 2(\frac{0.001}{0.3}) + \frac{0.02}{5} = 0.005 + 0.00667 + 0.004 = 0.01567 \approx 1.6\% \).
