Given:

            Mass per unit length of belt (m) = 1.50kg/m

            Velocity of the belt (v) = 10m/s

            Now, centrifugal tension is given by,

             (T_C) = mv² = 1.5 x 10² = 150N           

Hence, the correct option is (A).

..Method 2.

The optimum velocity of the belt,

Centrifugal force (or tension) is given by,

Note : The above velocity equation is to be used in case of maximum power transmission.