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Physics 203 Review Questions - Final - 1
1. Block A is resting on Block B, which is resting on a frictionless surface. Block B is
pulled to the right using a rope. There is friction between block A and B. Assign
masses and frictional coefficients to the objects, then calculate what the maximum
acceleration of block B can be, so that block A does not slip.
2. How far above the earth's surface should you go in order reduce 'little g' by 5
percent? How much would a 20 kg ball 'weigh' at this location?
3. A ball is dropped from a height of 4 meters and bounces back off the ground to a
height of 2.5 meters. What fraction of the initial energy is lost? What is the speed of
the ball right before it bounces? How would you explain this loss of energy?
4. A long jumper in track and field can raise her center of mass to 0.95 m above its
original location. If the jumpers velocity at that location is 5.5 m/s, how fast was her
launch speed?
5. A package is dropped on a conveyer belt that is moving at 3 m/s. Its mass is 15 kg
and it has a
and a
. For what distance is the package skidding before it
starts moving smoothly on the belt?
6. Two boxes are connected with a string. The string is hanging on
a pulley so when one box goes down, the other box goes up. If
the masses of the two boxes are 1.2 and 3.2 kg, the system will
clearly not be in equilibrium, and an acceleration will happen. The
pulley is suspended from the ceiling by the rope L. What is the
tension in that rope L while the masses are accelerating?
7. A solid sphere (eg. a bowling ball) is rolling at 3 m/s. If its mass is 8 kg, and its
radius is 10 cm, what is its total kinetic energy?
8. An object hangs from a scale that is essentially a spring. The scale reads 30 N in air,
20 N when this object is immersed in water, and 24 N when the object is immersed in
another liquid of unknown density. What is the density of that other liquid?
9. A large ocean liner has an engine with a maximum power of 92 MW at a cruising
speed of 32.5 knots. What forward force is exerted on the ship at this speed? (1 knot
= 1.852 km/h)
10. Sketch the following plots:
A. Plot the velocity as a function of time for an object shot straight up in the air
to a maximum height . Use marker values in terms of to label the vertical and
horizontal axes.
B. There are many planets an other rocks orbiting the sum. Plot the average
speed of such an orbiting body as a function of position away from the sun.
(assume circular orbits)
C. A train is moving at constant velocity in the positive direction. At time it
begins to slow down by decelerating at a constant rate until it is at rest at the
station. Plot its position as a function of time.
D. A car is accelerating at a constant rate. Plot its kinetic energy as a function of
time.
E. A ladybug is crawling outward from the center of a record while it is rotating
at a constant . Plot the centripetal acceleration of the ladybug as she moves
away from the center of the record.
F. You're pushing a box along a frictionless floor over a distance . You're taller
than the box, so you are pushing down on a angle with respect to the horizontal.
The box starts from rest. Plot the box's final speed as a function of the
magnitude of the pushing force. Plot the box's final speed as a function of the
angle between your applied force and the horizontal floor.
G. Plot the total energy (KE + PE) of a ball as it rolls down a ramp, as a
function of distance travelled along the surface of the ramp.
H. Plot the potential energy of a mass on a spring as a function of time.
I. A pendulum clock is being moved to a chalet up on the top of a large
mountain in Switzerland. Plot its period as a function of position up the
mountain. (i.e. as it gets further away from the center of the earth)
J. Plot the buoyancy force on a wooden block as a function of depth under
water.
K. Plot the water pressure a function of depth under the surface of the water.
L. Plot the period of a mass on a spring as a function of 1) the mass of the mass,
and 2) the spring constant, and 3) the amplitude of oscillation.
M. Plot the angular displacement, velocity, and acceleration as a function of time
for a hoop rolling down a ramp.