Question

A chain of $125m$ links in $1.25m$ long and has a mass of $2kg$. With the ends fastened together, it is set rotating at $3000rev/min$. The centripetal force on each link is :

• A. $3.14N$
• B. $314N$
• C. $\frac{1}{3.14}N$
• D. $\frac{1}{314}N$

Answer 1

Answer: (B)

$314N$

Given,

$\omega =3000rev/min$

$\omega =\frac{3000\times 2\pi }{60}=100\pi rad/s$

Mass of each link, $m=\frac{2}{125}kg$

Length of chain, $L=2\pi r=1.25$

radius, $r=\frac{1.25}{2\pi }m$

The total centripetal force,

$F=m{\omega }^{2}r$

$F=\frac{2}{125}\times 100\times 100{\pi }^2\times \frac{1.25}{2\pi }$

$F=314N$

The correct option is B.