Question

A beam of length l lies on the +x axis with its left end on the origin. A cable pulls the beam in y-direction with a force F = F₀ $\left( 1–\frac{x}{\mathcal{l}} \right)$. If the axis is fixed at x = 0 then find the torque –

• A. – F₀l
• B. $\frac{F_{0}\mathcal{l}}{2}$
• C. – $\frac{F_{0}\mathcal{l}}{2}$
• D. None of these

Answer 1

Answer: (B)

$\frac{F_{0}\mathcal{l}}{2}$

Answer 2

Torque t = $\int_{}^{}{d\tau}$ = $\int_{0}^{\mathcal{l}}{Fx}$ = $\frac{F_{0}\mathcal{l}}{2}$