Question

Quesiton A. Two objects are attracting each other with a certain gravitational force. If the original force between the two objects is 0.82 N , and the distance is tripled, what is the new gravitational force between the objects?

Question B. A bowling ball weighing 71.2 N is attached to the ceiling by a 4.00 m rope. The ball is pulled to one side and released; it then swings back and forth like a pendulum. As the rope swings through its lowest point, the speed of the bowling ball is measured at 4.40 m/s .

-At that instant, find the magnitude of the acceleration of the bowling ball.?

-At that instant, find the tension in the rope. ?

Answer 1

At this instant the object is moving in a circular path

so a = v^2/r

= 4.40^2 / 4.00 = 4.84m/s^2

The direction when it is in circular motion at constant speed is always toward the center of the circle.

The rope must provide sufficient force to overcome gravity plus enough more to accelerate it in a circle.

If gravity needs 71.2 N then the mass of the object must be 71.2/9.8 = 7.27Kg

m*a=F(up) 7.27*4.84= 35.18 N

N(up) + W (down) = Tension 35.18+ 71.2 = 106.38Tension