# physics

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sorry i have about 5 questions on this homework packet that i just can't figure out.... hope you can help me

A bowling ball (mass = 7.2 kg, radius = 0.12 m) and a billiard ball (mass = 0.41 kg, radius = 0.028 m) may each be treated as uniform spheres. What is the magnitude of the maximum gravitational force that each can exert on the other?

Three uniform spheres are located at the corners of an equilateral triangle. Each side of the triangle has a length of 1.50 m. Two of the spheres have a mass of 3.20 kg each. The third sphere (mass unknown) is released from rest. Considering only the gravitational forces that the spheres exert on each other, what is the magnitude of the initial acceleration of the third sphere?

A 40 kg crate rests on a horizontal floor, and a 72 kg person is standing on the crate.
(a) Determine the magnitude of the normal force that the floor exerts on the crate.
(b) Determine the magnitude of the normal force that the crate exerts on the person.

The drawing shows a circus clown who weighs 785 N. The coefficient of static friction between the clown's feet and the ground is 0.48. He pulls vertically downward on a rope that passes around three pulleys and is tied around his feet. What is the minimum pulling force that the clown must exert to yank his feet out from under himself?

A box is sliding up an incline that makes an angle of 18.0° with respect to the horizontal. The coefficient of kinetic friction between the box and the surface of the incline is 0.180. The initial speed of the box at the bottom of the incline is 1.70 m/s. How far does the box travel along the incline before coming to rest?

sorry i've just been trying to figure them out but managed nothing.. hope you can help

• physics - ,

did you ever figure out the one about the uniform spheres? i have the same problem for homework

• physics - ,

A bucket of mass M = [05] kg is attached to a
second bucket of mass m = 3:52 kg by an ideal string. The
string is hung over an ideal pulley as shown in the gure.
Mass M is started with an initial downward speed of
2.13 m/s. What then is the speed (m/s) of mass M after it
has moved 2.47 meters?