Mathematics in Physics

JEE Main level, single correct, medium

61 of 121

Question 61 of 121

The maximum percentage error in the measurment of density of a wire is [Given, mass of wire =(0.60±0.003)g=(0.60 \pm 0.003) \mathrm{g}
radius of wire =(0.50±0.01)cm=(0.50 \pm 0.01) \mathrm{cm}
length of wire =(10.00±0.05)cm]=(10.00 \pm 0.05) \mathrm{cm}]

Show answer and solution

Answer: (B) 5

d=m vol. =mπR2ℓ⇒ dρρ=dmm+2dRR+dℓℓ⇒dρρ=(0.0030.6+2×0.010.5+0.0510)100=5%\begin{aligned} & \mathrm{d}=\frac{\mathrm{m}}{\text { vol. }}=\frac{\mathrm{m}}{\pi \mathrm{R}^2 \ell} \Rightarrow \frac{\mathrm{~d} \rho}{\rho}=\frac{\mathrm{dm}}{\mathrm{m}}+\frac{2 \mathrm{dR}}{\mathrm{R}}+\frac{\mathrm{d} \ell}{\ell} \\ & \Rightarrow \frac{\mathrm{d} \rho}{\rho}=\left(\frac{0.003}{0.6}+\frac{2 \times 0.01}{0.5}+\frac{0.05}{10}\right) 100=5 \%\end{aligned}

JEE Main question paper PDF

Open a shift to read the full paper on this page, or download it.

JEE Main 2025 Apr 2 Shift 1 question paper

Open Download PDF

Opening paper…

Explain it as a whiteboard videoStep-by-step, in Hinglish or English. Your first video needs no login.Solved it on paper but got it wrong?Upload a photo of your working. Mistake Doctor marks the exact line that broke.

More Physics practice

JEE Main Physics practice question on Mathematics in Physics (Errors of Measurement), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.