A heavy ball with a weight of 150 N is hung from the ceiling of a lecture hall on a 4.6-m-long rope. The ball is pulled to one side and released to swing as a pendulum, reaching a speed of 5.1 m/s as it passes through the lowest point. What is the tension in the rope at that point?

236.5 N

Explanation:

The tension in the rope will be given by

where T is the tension on the rope, m is the mass of the ball, v is the speed of the ball of the ball at the lowest point and r is the length of the ball.

Since F=mg then making m the subject, where F is the force and g is acceleration due to gravity. Now replacing m with the above in the dirst equation then

Substituting 150 N for F, 9.81 for g, 5.1 m/s for v and 4.6 m for L then