All work on this exam must be your own. You may use a
calculator and a 3"X5" card of equations. Clearly indicate your **final**
answer for each question.

**PART I** -- EQUILIBRIUM, ELASTICITY, AND GRAVITY

__Section 1__: Multiple choice. No partial credit will
be given for this section. Circle **only one** answer for each question.
(2 pts each)

b)* 19%* of the way to the moon.

c)* 80/81 *of the way to the moon.

d)* 9/10* of the way to the moon.

b) The upper part of the board is in compression; the lower part of the board is in tension.

c) The upper part of the board is in tension; the lower part of the board is in compression.

d) The upper part of the board is in compression; the
lower part of the board is also in compression.

b) 1/3 as much.

c) 9 times as much.

d) the same amount.

c) The ladder can be in equilibrium if the wall exerts no vertical force on it.

d) The ladder cannot be in equilibrium.

b) A vertical component upward, and a horizontal component to the left.

c) A vertical component downward, and a horizontal component to the right.

a) A vertical component downward, and a horizontal component
to the left.

b) The satellites must have the same speed.

c) The satellites must be the same distance from the center of the earth.

d) All of the above.

b) the same as

c) greater than

d) not enough info is given to determine the answer.

Partial credit will be given for this section. **Show
ALL WORK** and **JUSTIFY** all answers. Be sure your answers include
**UNITS** where appropriate.

For the following problems, you may need the value of the gravitational constant:

8) NOTE: since we did not cover oscillations in 201 this
year, you might be better off using one of the equilibrium problems in
the text as an example problem.

A 44g block is hanging at equilibrium from a spring which
has a spring constant of 2.7 N/mm. The block is then pulled down by 1.0
cm, released from rest, and allowed to oscillate.

b) Plot the displacement of the block as a function of
time, neglecting air resistance. Your plot should have a scale and units
for both axes. (This is **not** a rough sketch).

c) Plot the velocity of the block as a function of time,
neglecting air resistance. Your plot should have a scale and units for
both axes. (This is **not** a rough sketch).

b) What is the ratio Delta-L_{A}/Delta-L_{B}
(see figure).

10) Given the following astronomical information:

Mass of Earth: M_{E} = 5.98 X 10^{24}
kg

Radius of Earth: r_{E} = 6.37 X 10^{6}
m

Radius of Earth's orbit around sun: R_{E} = 1.5
X 10^{11} m

Mass of Jupiter: M_{J} = 318M_{E}

Radius of Jupiter: r_{J} = 11.2r_{E}

Radius of Jupiter's orbit around sun: R_{J} =
5.20R_{E}

The Earth and Jupiter have approximately circular orbits around the Sun. (Assume the Sun, the Earth, and Jupiter are in a line, in that order.)

b) When a rocket of mass 4400 kg is still on Earth, what is the gravitational force of the Earth on the rocket?

b) Find the maximum angular acceleration of the pendulum bob.

c) Describe two things you could do to *increase*
the maximum acceleration of the pendulum bob.

__Section 1__: Multiple choice. No partial credit will
be given for this section. Circle **only one** answer for each question.
(2 pts each)

12) A block of mass m is pulled at constant velocity of
1.0 m/s along a rough horizontal floor by an applied force T as shown.
What is the magnitude of the frictional force?

a) m_{ s}mg

b) T

c) zero

d) mg

b) is the rate at which work is done on the object.

c) equals the time rate of change of momentum of the object.

d) has the dimensions of momentum multiplied by time.

14) Given the following sketch of an object's velocity
as a function of time, what is (are) the time interval(s) during which
the object's **speed** is increasing?

a) 0s to 2s.

b) 0s to 2s and 3.3s to 4s.

c) 2s to 4s.

d) 0s to 1s and 3.3s to 4s.

Partial credit will be given for this section. **Show
ALL WORK** and **JUSTIFY** all answers. Be sure your answers include
**UNITS** where appropriate. (5 pts each)

16) An object is thrown vertically down with an initial
speed of 1.0 m/s. How far will it have travelled after 5.0 s?

17) A disk with a rotational inertia of 5.0 kg m^{2}
and a radius of 0.25 m rotates about an axis perpendicular to the disk
and through its center. A 2.0 N force is applied tangentially at the rim.
What is the angular acceleration of the disk?

18) Two blocks are moving toward each other. One block has a mass of 1.2 kg and is initially moving at 1.7 m/s; after the collision it is moving in the same direction at 1.38 m/s. The other block has a mass of 0.45 kg, and is initially moving at 0.16 m/s. What is its final velocity (magnitude and direction)?