Q. A rope of mass 0.1 kg is connected at the same height of two opposite walls. It is allowed to hang under its own weight. At the contact point between the rope and the wall, the rope makes an angle $\theta = 10{^\circ}$ with respect to the horizontal. The tension in the rope at its midpoint between the wall is
A) $2.78\ N$
B) $2.56\ N$
C) $2.82\ N$
D) $2.71\ N$
Explanation
(c) Mass of rope, $m = 0.1\ kg,\ \theta = 10{^\circ}$
[image:5_image201.emf]
From figure, $2T\sin\theta = mg$
$\Rightarrow T = \frac{mg}{2\sin\theta} = \frac{0.1 \times 9.8}{2\sin{10{^\circ}}} = 2.82\ N$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.