Answer:
4.62N
Step-by-step explanation:
Since the motion covers 1 circle (or 2π rad) per 0.8 seconds, its angular velocity is

Radius of the circular motion is r = 75 cm or 0.75m. We can calculate the centripetal acceleration of this mass

From Newton's 2nd law, we calculate the centripetal force, which is also the tension of the string:
