Answer
a) decreases
b) $35N$
Work Step by Step
(a) We know that when the wire is shortened then the angle made by the rod increases and as a result the tension in the wire decreases.
(b) We can calculate the tension as follows:
$T=\frac{mg(\frac{L}{2})cos35^{\circ}}{r}$
We plug in the known values to obtain:
$T=\frac{(3.7Kg)(9.81m/s^2)(0.6m)cos35^{\circ}}{0.51m}$
$T=35N$
