Answer
(a) $T = \frac{mv^2}{L}$
(b) $T = \frac{mv^2}{L~cos^2~\theta}$
Work Step by Step
(a) The rope's tension provides the centripetal force to keep the rock moving around in a circle. We can find the tension in the rope:
$T = \frac{mv^2}{L}$
(b) The horizontal component of the rope's tension provides the centripetal force to keep the rock moving around in a circle. We can find the tension in the rope:
$T~cos~\theta = \frac{mv^2}{L~cos~\theta}$
$T = \frac{mv^2}{L~cos^2~\theta}$
