Question

A ball is fixed to the end of a string which is attached to the ceiling at point P. As the drawing shows, the ball is projected downward at A with the lunch speed Vo. Traveling on a circular path, the ball comes to a halt at point B. What enables the ball to reach point B, which is above point A. Ignore friction and air resistance. a. The balls initial kinetic energy. b. The balls initial gravitational potential energy. c. The work done by the tension in the string. d. The work done by the gravitational force.

Answer 1

a. The balls initial kinetic energy.

Step-by-step explanation:

As we know that initially speed is given to the ball downwards so that it moved in a circle so then finally reached to point B

Now given that point B is higher than the initial position A from which it is projected

Now by energy conservation we know that

`K_i + U_i = K_f + U_f`

since final speed is zero so we have

`K_i + mgh_a = 0 + mgh_b`

`h_b = h_a + (K_i)/(mg)`

so from above equation we can say that since initial kinetic energy is given to the ball so it will be able to reach the point which is higher than its initial position

so correct answer is

a. The balls initial kinetic energy.