Two blocks of masses $1 \mathrm{~kg}$ and $2 \mathrm{~kg}$ are connected by a metal wire going over a smooth pulley. The breaking stress of metal is $\frac{40}{3 \pi} imes 10^6 \mathrm{Nm}^{-2}$. What should be the minimum radius of wire used if it should not break? $\left(g=10…

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Two blocks of masses $1 \mathrm{~kg}$ and $2 \mathrm{~kg}$ are connected by a metal wire going over a smooth pulley. The breaking stress of metal is $\frac{40}{3 \pi} 	imes 10^6 \mathrm{Nm}^{-2}$. What should be the minimum radius of wire used if it should not break? $\left(g=10 \mathrm{~ms}^{-2}ight)$

Aicharya · Accepted Answer

$\begin{aligned} & 	ext { Breaking stress }=\frac{F}{A} \ & 	ext { Here, breaking stress }=\frac{40}{3 \pi} 	imes 10^6 \mathrm{Nm}^{-2} \ & \Rightarrow \quad \frac{40}{3 \pi} 	imes 10^6=\frac{3 	imes 10}{\pi r^2} \ & \Rightarrow \quad r^2=\frac{9}{4} 	imes 10^{-6}\end{aligned}$ or $\quad \begin{aligned} r & =1.5 	imes 10^{-3} \mathrm{~m} \ & =1.5 \mathrm{~mm}\end{aligned}$

Two blocks of masses $1 \mathrm{~kg}$ and $2 \mathrm{~kg}$ are connected by a metal wire going over a smooth…

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