Rotational Motion Question 4
Question 4 - 25 January - Shift 1
An object of mass $8 kg$ is hanging from one end of a uniform rod CD of mass $2 kg$ and length $1 m$ pivoted at its end $C$ on a vertical wall as shown in figure. It is supported by a cable $A B$ such that the system is in equilibrium. The tension in the cable is :
(Take $g=10 m / s^{2}$ )
(1) $240 N$
(2) $90 N$
(3) $300 N$
(4) $30 N$
Show Answer
Answer: (3)
Solution:
Formula: Torque
Taking torque about point $C$
$\frac{T}{2} \times 60=20 \times 50+80 \times 100$
$\Rightarrow 3 T=100+800$
$\Rightarrow=300 N$
