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robbieholtz

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**Need Help With College Physics!!!!!!!!!!**

alright i have some homework questions i need help with, any help would be greatly appreciated:

1.A 300 g baseball traveling at 30 m/s is struck by a bat in the direction from which it came at 40 m/s. Find the impulse of the force on the baseball.

2.A solid cylinder of mass 8 kg and diameter 20 cm is rotated about an axis parallel to its central axis at a distance of 10 cm from the cylinder. The rotational inertia of the cylinder about the parallel axis is:

3.If a solid cylinder, a hoop and a solid sphere of the same mass are rolled down simultaneously from the same height on an inclined plane, in which order will the objects reach the bottom of the incline?

4.A 3 kg bowling ball traveling with a velocity of 3 m/s collides head-on with another bowling ball of the same mass traveling with a velocity of - 2 m/s. If the collision is perfectly elastic, the velocities of the bowling balls after the collision is:

5.The center of mass of three objects is located at (1, 0). One object with a mass of 5.0 kg is at (- 2, - 1) and a second object with a mass of 2.0 kg is at (0, 0). Find the coordinates of the third mass of 3.0 kg.

6.Water is pumped through a pipe to a tank at the top of a building. The pressure of the water at ground level is 2.2 x 105 Pa and at the tank, the pressure is atmospheric. If the diameter of the pipe is the same throughout, find the height at which the tank is located. Atmospheric pressure may be assumed as 1.0 x 105 Pa and g as 9.8 m/s2.

7.A force of 1.0 x 103 N is applied to a steel rod of length 1 m and a circular cross-section of area 10 cm2. Find the elongation of the rod. Young's modulus for steel is 2.0 x 1011 Pa.

8.A 200 g ball hits a wall perpendicularly with a velocity of 30 m/s and rebounds back perpendicularly with a velocity of 20 m/s. If the collision lasts for 5 milliseconds, find the average force exerted by the ball on the wall.

9.A disk with a mass of 50 kg and radius 0.40 m is rotated about its axis by a motor. The disk starts from rest and rotates at 120 rev/min in 10 s. Find the torque, assuming it to be a constant.

10.The magnitude of the momentum of a particle is 32 kg m/s at a certain instant. If the velocity has a magnitude of 20 m/s at that instant, the mass of the particle is:

11.A star rotates about its axis through a diameter once in 50 days. At the end of its life, the star collapses to one-hundredth of its original diameter. The rate of rotation of the collapsed star will be:

12.The crankshaft of an engine is accelerated from rest at the uniform rate of 4.0 rad/s2 for 30 s. Find the rotational speed of the crankshaft at the end of 30 s in rev/min.

13.The gauge pressure at a depth of 17 m in water is equal to:

14.A uniform solid sphere of mass 5 kg and radius 30 cm is rotating about an axis through its center at the rate of 180 rev/min. Find the kinetic energy of the sphere. The rotational inertia of a uniform sphere is 2/5 MR2.

15.A log of wood is floating in water with 40% of its volume above the surface of the water. If the volume of the log is 0.4 m3, find the mass of the log.

alright thats it, PLEASE HELP ME with any of these THANKS!!!!!!!!!