Question

A steering wheel of diameter $0.5m$ is rotated anti-clockwise by applying two forces each of magnitude $5N$. Calculate the moment of couple applied :

• A. $5N$ $m$
• B. $25N$ $m$
• C. $50N$ $m$
• D. $2.5N$ $m$

Answer 1

The correct option is D $2.5N$ $m$

Given that diameter of 0.5 m wheel for which we are applying a force of 5 N. We know that moment of force is given by $r\times F$

Now there are two forces and from right-hand thumb rule their moments will get added Hence

$moment=0.25\times 5+0.25\times 5=2.5N-m$. Hence we have a magnitude of $2.5Nm$.