AP Physics 1 Unit 4 Progress Check A and B Answered
2023.
AP Physics 1 Unit 4 Progress Check A
A block of mass M on an inclined surface is attached to a spring of negligible
mass, as shown. The other end of the spring is attached to a wall, and there is
negligible friction between the block and the incline. The block is pulled to a
position such that the spring is stretched from its equilibrium position. The block
is then released from rest. Which of the following systems can be classified as a
closed system?
A system consisting of the block, spring, and Earth
The total mechanical energy of a system as a function of time is shown in the
graph. Which of the following statements is true regarding the system?
The system should be classified as an open system because mechanical energy can be
added and removed from the system.
A planet orbits a star along an elliptical path from point X to point Y, as shown in
the figure. In which of the following systems does the total mechanical energy of
the system remain constant?
The closed system containing the planet and the star
A 5 kg object near Earth's surface is released from rest such that it falls a
distance of 10 m. After the object falls 10 m, it has a speed of 12 m/s. Which of the
following correctly identifies whether the object-Earth system is open or closed
and describes the net external force?
The system is open, and the net external force is nonzero.
A toy car has an initial acceleration of 2m/s2 across a horizontal surface after it is
released from rest. After the car travels for a time t=5 seconds, the speed of the
car is 25m/s. Is the system consisting of only the car an open system or a closed
system, and why?
Open system, because an external force is applied to the car that causes it to
accelerate.
A student performs an experiment in which a ball travels in a perfect circle. The
ball is attached to a string and travels in the horizontal, circular path, as shown in
Figure 1. At time t0, the ball has a speed ν0. During the time interval of 0s to 2s,
the force of tension in the string is recorded and graphed, as shown in Figure 2.
Is the system consisting of the ball, string, and student an open system or closed
system, and why?
Open system, because the force due to gravity from Earth is an external force that is
exerted on the ball-string-student system
A student must determine the effect of friction on the mechanical energy of a
small block as it slides up a ramp. The block is launched with an initial speed v0
from point A along a horizontal surface of negligible friction. It then slides up a
ramp, where friction is not negligible, that is inclined at angle θ with respect to the
horizontal, as shown in the figure. The student measures the maximum vertical
height h attained by the block while on the ramp, labeled as point B in the figure.
, At point B, the block comes to rest. The student performs three trials with the
ramp at different angles, launching the block at the same initial speed v0 for each
trial. The results from the trials are displayed in the table.
How should the student use the data collected and the known quantities from the
experiment to determine the total mechanical energy of the block-ramp-Earth
system for all trials in the experiment?
Use K=1/2 mv2K=1/2mv2 with the block's initial speed for one trial because the initial
speed is the same in all trials.
A student must determine the effect of friction on the mechanical energy of a
small block as it slides up a ramp. The block is launched with an initial speed v0
from point A along a horizontal surface of negligible friction. It then slides up a
ramp, where friction is not negligible, that is inclined at angle θ with respect to the
horizontal, as shown in the figure. The student measures the maximum vertical
height h attained by the block while on the ramp, labeled as point B in the figure.
At point B, the block comes to rest. The student performs three trials with the
ramp at different angles, launching the block at the same initial speed v0 for each
trial. The results from the trials are displayed in the table.
Consider the trial with the 45° ramp. Suppose the block is launched up the ramp
such that it comes to rest at point B and then travels down the ramp. Which of the
following best describes the block's kinetic energy KA when it reaches point A at
the bottom of the ramp in comparison to the initial kinetic energy K0 before it
travels up the ramp?
KA<K0KA<K0 , because the force of friction removes mechanical energy from the
block-ramp-Earth system on its way up the ramp and back down the ramp.
A student must determine the effect of friction on the mechanical energy of a
small block as it slides up a ramp. The block is launched with an initial speed v0
from point A along a horizontal surface of negligible friction. It then slides up a
ramp, where friction is not negligible, that is inclined at angle θ with respect to the
horizontal, as shown in the figure. The student measures the maximum vertical
height h attained by the block while on the ramp, labeled as point B in the figure.
At point B, the block comes to rest. The student performs three trials with the
ramp at different angles, launching the block at the same initial speed v0 for each
trial. The results from the trials are displayed in the table.
Consider the trial in which the ramp is at a 20° angle with the horizontal. The
surface of the ramp has been replaced with a surface in which frictional forces
are considered to be negligible. If the mass of the block is doubled and the initial
launch speed is doubled, how could the student predict the new vertical of the
block at point B?
Use 12mv2initial=mgyfinal12mvinitial2=mgyfinal to solve for yfyf
A block on a rough, horizontal surface is attached to a horizontal spring of
negligible mass. The other end of the spring is attached to a wall. The spring is
compressed such that the block is located at position X. When the block-spring
system is released, the block travels to the right through position Y and
continues to travel to the right through position Z. Free body diagrams for the
block at positions X, Y, and Z are shown in the figure. At which position does the
block have the greatest kinetic energy?
2023.
AP Physics 1 Unit 4 Progress Check A
A block of mass M on an inclined surface is attached to a spring of negligible
mass, as shown. The other end of the spring is attached to a wall, and there is
negligible friction between the block and the incline. The block is pulled to a
position such that the spring is stretched from its equilibrium position. The block
is then released from rest. Which of the following systems can be classified as a
closed system?
A system consisting of the block, spring, and Earth
The total mechanical energy of a system as a function of time is shown in the
graph. Which of the following statements is true regarding the system?
The system should be classified as an open system because mechanical energy can be
added and removed from the system.
A planet orbits a star along an elliptical path from point X to point Y, as shown in
the figure. In which of the following systems does the total mechanical energy of
the system remain constant?
The closed system containing the planet and the star
A 5 kg object near Earth's surface is released from rest such that it falls a
distance of 10 m. After the object falls 10 m, it has a speed of 12 m/s. Which of the
following correctly identifies whether the object-Earth system is open or closed
and describes the net external force?
The system is open, and the net external force is nonzero.
A toy car has an initial acceleration of 2m/s2 across a horizontal surface after it is
released from rest. After the car travels for a time t=5 seconds, the speed of the
car is 25m/s. Is the system consisting of only the car an open system or a closed
system, and why?
Open system, because an external force is applied to the car that causes it to
accelerate.
A student performs an experiment in which a ball travels in a perfect circle. The
ball is attached to a string and travels in the horizontal, circular path, as shown in
Figure 1. At time t0, the ball has a speed ν0. During the time interval of 0s to 2s,
the force of tension in the string is recorded and graphed, as shown in Figure 2.
Is the system consisting of the ball, string, and student an open system or closed
system, and why?
Open system, because the force due to gravity from Earth is an external force that is
exerted on the ball-string-student system
A student must determine the effect of friction on the mechanical energy of a
small block as it slides up a ramp. The block is launched with an initial speed v0
from point A along a horizontal surface of negligible friction. It then slides up a
ramp, where friction is not negligible, that is inclined at angle θ with respect to the
horizontal, as shown in the figure. The student measures the maximum vertical
height h attained by the block while on the ramp, labeled as point B in the figure.
, At point B, the block comes to rest. The student performs three trials with the
ramp at different angles, launching the block at the same initial speed v0 for each
trial. The results from the trials are displayed in the table.
How should the student use the data collected and the known quantities from the
experiment to determine the total mechanical energy of the block-ramp-Earth
system for all trials in the experiment?
Use K=1/2 mv2K=1/2mv2 with the block's initial speed for one trial because the initial
speed is the same in all trials.
A student must determine the effect of friction on the mechanical energy of a
small block as it slides up a ramp. The block is launched with an initial speed v0
from point A along a horizontal surface of negligible friction. It then slides up a
ramp, where friction is not negligible, that is inclined at angle θ with respect to the
horizontal, as shown in the figure. The student measures the maximum vertical
height h attained by the block while on the ramp, labeled as point B in the figure.
At point B, the block comes to rest. The student performs three trials with the
ramp at different angles, launching the block at the same initial speed v0 for each
trial. The results from the trials are displayed in the table.
Consider the trial with the 45° ramp. Suppose the block is launched up the ramp
such that it comes to rest at point B and then travels down the ramp. Which of the
following best describes the block's kinetic energy KA when it reaches point A at
the bottom of the ramp in comparison to the initial kinetic energy K0 before it
travels up the ramp?
KA<K0KA<K0 , because the force of friction removes mechanical energy from the
block-ramp-Earth system on its way up the ramp and back down the ramp.
A student must determine the effect of friction on the mechanical energy of a
small block as it slides up a ramp. The block is launched with an initial speed v0
from point A along a horizontal surface of negligible friction. It then slides up a
ramp, where friction is not negligible, that is inclined at angle θ with respect to the
horizontal, as shown in the figure. The student measures the maximum vertical
height h attained by the block while on the ramp, labeled as point B in the figure.
At point B, the block comes to rest. The student performs three trials with the
ramp at different angles, launching the block at the same initial speed v0 for each
trial. The results from the trials are displayed in the table.
Consider the trial in which the ramp is at a 20° angle with the horizontal. The
surface of the ramp has been replaced with a surface in which frictional forces
are considered to be negligible. If the mass of the block is doubled and the initial
launch speed is doubled, how could the student predict the new vertical of the
block at point B?
Use 12mv2initial=mgyfinal12mvinitial2=mgyfinal to solve for yfyf
A block on a rough, horizontal surface is attached to a horizontal spring of
negligible mass. The other end of the spring is attached to a wall. The spring is
compressed such that the block is located at position X. When the block-spring
system is released, the block travels to the right through position Y and
continues to travel to the right through position Z. Free body diagrams for the
block at positions X, Y, and Z are shown in the figure. At which position does the
block have the greatest kinetic energy?
