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1. A 4.5 kg block is at rest on a table when it is attached to a second mass, m2 hanging over a pulley. The static coefficient of friction between the block and the table is 0.56 and kinetic coefficient is 0.42, respectively. The hanging mass, m2 is chosen to be 2.4 kg.
a) Will this choice for m2 set the system in motion?
b) If the system is set in motion, find the acceleration of the block and the tension in the string.

2. An object of mass 5 kg is acted upon by four forces, each of magnitude 10 N.
Which of the following could NOT be the acceleration of the object?
A) 0 m/s2 B) 2m/s2 C) 4 m/s2 D) 8 m/s2 E) 10 m/s2

3. Two metal spheres with the same diameter, one hollow and on solid, falls through
air from the 10th floor of a building.
A) The solid sphere will land first because it experiences less air resistance.
B) The hollow sphere will land first because it experiences less air resistance.
C) The solid sphere will land first because it has the largest weight, and the least effect of the air resistance.
D) They will land at the same time, because all objects fall with the same acceleration.

4. An object of mass 5 kg is acted upon by four forces, each of magnitude 10 N.
Which of the following could NOT be the acceleration of the object?
A) 0 m/s2 B) 2m/s2 C) 4 m/s2 D) 8 m/s2 E) 10 m/s2

Passage for questions 5 and 6:
An object is dropped out of a high-flying balloon. It reaches terminal velocity after 8 seconds.

5. During which time interval does the object travel the greatest distance?
A) 0-1s B) 2-3 s C) 4-5 s D) 6-7 s E) 8-9 s

6. During which time interval does the object increase its velocity by the greatest amount?
A) 0-1s B) 2-3 s C) 4-5 s D) 6-7 s E) 8-9 s

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https://brainmass.com/physics/velocity/physics-270994

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Miscellaneous physics question

1. Competitive divers pull their limbs in a curl up their bodies when they do flips. Just before entering the water, they fully extend their limbs to enter straight down. Explain the effect of both actions on their angular velocity. What is the effect of these actions on their angular momentum?

2. What is the final velocity of a hoop that rolls without slipping down a 5.00 m high hill, starting from rest?

3. Three children are riding on the edge of a 1.60-m-radius, 100 kg merry-go-round, spinning at 20.0 rpm. The children have masses of 22.0, 28.0, and 33.0 kg. If the child with a mass of 28.0 kg moves to the center of the merry-go-round, what is the new angular velocity in rpm?

4. A ball slides up a ramp without friction. It is then rolled without slipping and with the same initial velocity up another ramp. In which case does it reach a greater height, and why?

5. (a) Calculate the angular momentum of the earth in its orbit around the sun. (b) Compare this with the angular momentum of the earth on its axis.

6. A yo-yo may be modeled as a small cylinder of mass 0.12 kg and radius 8.0 cm. (A) What is the rotational inertia of such a yo-yo? (B) As the yo-yo unwinds from the string, its angular speed goes up, from 0 to 40 radians per second in a period of 1.4 seconds. What is the net torque on the yo-yo? (C) What is the yo-yo's angular momentum at the end of the period described above? (D) When the yo-yo is rotating at 40 radians per second, how many revolutions is it making each second?

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