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Physics 150
Final
Fall 1999
NAME:_________________________
Useful Constants and Data
g = 9.81 m/s2
Part I
Choose the best answer
Multiple Choice
MC
P
(4 points. ea.)
___ 1. Fluid at rest at the bottom of a container is
(A) under less pressure than the fluid at the top.
(B) under the same pressure as the fluid at the top.
(C) under more pressure than the fluid at the top.
(D) any of the above depending on circumstances.
___ 2. The three containers shown at right are filled with water to
the same height. The one with the greatest pressure at the
bottom is
(A) container A.
(B) container B.
(C) container C.
(D) all have the same pressure at the bottom.
A
B
C
___ 3. Buoyancy occurs because, with increasing depth in a fluid,
(A) the pressure increases.
(B) the pressure decreases.
(C) the density increases.
(D) the density decreases.
___ 4. Bernoulli’s Equation is based upon
(A) conservation of energy.
(B) conservation of momentum.
(C) the second law of motion.
(D) the third law of motion.
___ 5. The amplitude of a simple harmonic oscillator does not affect its
(A) frequency.
(B) maximum speed.
(C) maximum acceleration.
(D) maximum KE.
___ 6. The total energy (KE +PE) of a simple harmonic oscillator is
(A) a maximum when the mass is at the equilibrium position.
(B) a maximum when the mass is at its maximum displacement from equilibrium.
(D) constant.
(D) always zero
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Physics 150
Final
Fall 1999
___ 7. A pendulum clock, which keeps correct time on earth, is taken to the surface of the moon. The
clock will
(A) run fast (i.e. clock’s “seconds” are shorter than real seconds).
(B) run slow (i.e. clock’s “seconds” are longer than real seconds).
(C) still run correctly.
(D) will not run at all because there is no gravity on the moon.
___ 8. The speed of a wave on a stretched string depends upon
(A) the tension in the string.
(B) the wavelength of the wave.
(C) the amplitude of the wave.
(D) all of the above.
___ 9. The higher the frequency of a wave,
(A) the higher its speed.
(B) the shorter its wavelength.
(C) the greater its amplitude.
(D) the longer its period.
___ 10. In a transverse wave, the individual particles of the material making up the medium through
which the wave travels
(A) move in circles.
(B) move in ellipses.
(C) move parallel to the wave’s velocity.
(D) move perpendicular to the wave’s velocity.
(E) none of the above.
___ 11. The tone (or pitch) of a wave depends upon its:
(A) frequency.
(B) amplitude.
(C) waveform.
(D) velocity.
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Final
___ 12. The displacement-time graph shown at right indicates
an object which
(A) is moving at constant velocity in the negative direction,
which then accelerates in the opposite direction, coming
to rest.
(B) is moving at constant velocity in the positive direction,
which then accelerates in the opposite direction, coming
to rest.
(C) is initially stationary, then begins accelerating in the
negative direction.
(D) is initially stationary, then begins accelerating in the
positive direction.
(E) none of the above.
Fall 1999
Displacement
Time
___ 13. Ball A thrown horizontally, and ball B is dropped from the same height at the same time. Then
(A) ball A will reach the ground first.
(B) ball B reach will reach the ground first.
(C) ball A and ball B will reach the ground simultaneously.
(D) which ever ball is heavier will reach the ground first.
(E) none of the above.
___ 14. As Dr. Gallis sits on a table in the front of the room (in equilibrium), the force that the table
exerts on Dr. Gallis is
(A) less than the force that Dr. Gallis exerts on the table.
(B) equal to the force that Dr. Gallis exerts on the table.
(C) greater than the force that Dr. Gallis exerts on the table.
(E) none of the above.
___ 15. The work done in moving an object from point A to point B against a nonconservative force
(A) can be recovered by moving it from point B to point A.
(B) does depend upon the path the object takes moving from point A to point B.
(C) can not be written as a change in potential energy.
(D) all of the above.
(E) none of the above.
___ 16. In an inelastic collision
(A) momentum is conserved but KE is not.
(B) KE is conserved but momentum is not.
(C) both KE and momentum is conserved.
(D) neither KE nor momentum is conserved.
(E) none of the above is always true.
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Final
Fall 1999
___ 17. The centripetal force on a car rounding a curve on a level road is provided by
(A) gravity.
(B) friction between the tires and the road.
(C) the torque applied to the steering wheel.
(D) its brakes.
___ 18. A dropped pall loses PE as it falls. Gravity is an example of
(A) a conservative force.
(B) a nonconservative force.
(C) a dissipative force.
(D) momentum.
___ 19. The rotational analog of force in linear motion is
(A) moment of inertia.
(B) torque.
(C) angular momentum.
(D) angular speed.
___ 20. In an equilibrium problem, the point about which torques are calculated
(A) must pass through one end of the object.
(B) must pass through the objects center of mass.
(C) must intersect the line of action of at least one force acting on the object.
(D) may be located anywhere.
___ 21. A shear stress can only be supported in
(A) solids.
(B) solids and liquids.
(C) fluids.
(D) gases.
(E) all of the above.
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Physics 150
Final
Part II
Problems
Show all work. No work = no credit! (15 points each)
1. An uninflated 30.0 kg balloon is filled with 100 m3 of hydrogen.
(A) What is the weight of the (uninflated) balloon?
(B) What is the weight of the hydrogen in the balloon?
(C) What is the weight of the air displaced by the inflated balloon?
(D) What is the buoyant force on the balloon?
(E) What force is necessary to hold the balloon down?
Fall 1999
Useful numbers:mass density
Air
1.30 kg/m3
Hydrogen 0.090 kg/m3
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2. A water tank has 1.00 cm2 (1.00 x10-4 m2) hole located 2.00 m below the water surface.
(A) What is the speed of the water as it exits the hole?
(B) What is the flow rate of the water as it exits the hole?
(C) How many kilograms of water emerge from the hole each second? (the density of water is 1.00 kg/m3)
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Physics 150
Final
Fall 1999
3. A .100 Kg mass is suspended from a spring whose force constant is 40 N/m. The mass is then pulled
down by .0200 m and released.
(A) What is frequency of the oscillations?
(B) What is the amplitude of the oscillations?
(C) What is the maximum PE of the mass on the spring during the oscillations?
(D) What is the maximum KE of the mass on the spring during the oscillations?
(E) What is the maximum speed of the mass during the oscillations
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Physics 150
Final
Fall 1999
4. A steel wire 0.500 m long and 4.00 g in mass is under a tension of 100 N.
(A) What is the velocity of waves on the wire?
(B) What is wavelength of the fundamental mode of vibration?
(C) What is the frequency of the fundamental mode of vibration?
(D) What is the frequency of the first overtone?
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Final
Fall 1999
5. A beloved coffee mug slides (horizontally) off of a 1m high lab bench, and lands (mercifully intact)
on the ground 2m away .
(A) How long does it take the mug to hit the ground?
(B) What is the final vertical component of velocity?
(C) What is the horizontal component of velocity?
(D) How far from the building did the balloon land?
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Physics 150
Final
Fall 1999
6. An 5.0 kg mass is initially at rest when a 20.0 N force is applied over a distance of 8.0 m.
(A) What is the initial KE of the mass?
(B) What is the final KE of the mass?
(C) How much work is done on the object?
(D) What is the final speed of the object?
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Physics 150
Final
Fall 1999
7. A 7.0 kg bowling ball .15 m in radius rolls at a speed of 5 m/s.
(A) Determine the translational KE of the ball.
(B) What is the angular velocity of the rolling ball?
(C) Calculate the moment of inertia of the ball: for a uniform sphere I = 2/5 MR2
(D) What is the rotational KE of the ball?
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8. . Block A (mass = 4.00 kg) and Block B (mass = 8.00 kg) are suspended by a
string on either side of a friction-less pulley. Since they are tied together
(interacting through the tension in the string) they will accelerate at the same
rate.
(A) Draw a free body diagram for each block, indicating the forces acting on
each block.
(B) Determine the acceleration of the masses.
(C) Determine the tension in the string.
Fall 1999
A
B
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