Question

A chain of $125$ links is $1.25m$ long and has mass of $2kg$ with the ends fastened together. It is set for rotating at $50$ revolutions per second. The centripetal force on each link is

• A. $3.14N$
• B. $0.314N$
• C. $314N$
• D. None of these

Answer 1

Answer: (C)

circumference $=2\pi r=1.25m$
so radius $r=\frac{1 .25 m}{2 \pi }=0.199m$
Mass of each link is m $=\frac{2 kg \, }{125}$ $= 0.016 \, $ $kg$
angular velocity is $w=50$ revolutions per second = $50\times 2\pi rads^{- 1}=314rads^{- 1}$
The centripetal force on each link is $f=m \times r \times w^2=\left(0.016 \times 0.199 \times 314^2\right) \quad \mathrm{N}$
$f = 314$ $N$