Physics 72 Samplex Midyear 2016
Physics 72 Samplex Midyear 2016
Physics 72 Samplex Midyear 2016
College of Science
Physics 71
Set A
Second Long Exam
Midyear 2016
Name:
Instructor:
Section/Class Schedule:
Student Number:
Course:
College:
Midyear 2016
Physics 71
Instructions: Choose the letter of the best answer to each of the following questions. Use
No. 2 Pencil to shade your answer on the answer sheet. To change your answer, erase your
old answer neatly and shade the new one. Any form of cheating in examinations or any act
of dishonesty in relation to studies, such as plagiarism, shall be subject to disciplinary
action. Whenever applicable, use g = 9.80 m/s2 for the magnitude of acceleration due to
gravity. Following instructions is part of the examination.
C. 8 y + 2x
B. 10x 3y
D. 10x + 3y
For the next two questions, consider the following scenario: Manong pulled a box weighing
2.50 kg with a force of 10.0 N directed 40 above the horizontal.
2. Frictionless. What is the total work done on the box if Manong was able to move the box
3.00 m along the horizontal frictionless floor?
A. 30.0 J
B. 19.0 J
C. 23.0 J
D. 73.5 J
3. Frictionless-less. If however, the floor is rough, and the coefficient of friction between the
box and floor is 0.450 so that manong has to pull with a force of 20.0 N still directed 40
above the horizontal, what will be the total work done on the box?
A. 4.30 J
B. 12.9 J
C. 43.0 J
D. 46.0 J
4. Ariel. Ariel drives their family car to UP from his home. The mass of the car with Ariel
inside is 2.00 103 kg. What is the speed of Ariel and his car if their kinetic energy at the
UP gate is 56.2 kJ?
A. 56.2 m/s
B. 7.50 m/s
C. 5.30 m/s
D. 28.1 m/s
5. Push pa more. A 10 kg crate initially moves at 0.20 m/s to the right. An 8.0-N force
applied to the right. What is the final speed of the crate after moving 0.20 m?
A. 0.40 m/s
B. 0.60 m/s
A2
C. 0.80 m/s
D. 1.0 m/s
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Physics 71
B. 534 W
C. 941 W
D. 235 W
8. Battle of Bastards. Jon and Ramsay pushed an object from x = 0.00 m up to x = 8.00 m
with a net force profile shown in the figure below. Which of the following statements is/are
TRUE?
I. The work done by Jon is equal to the work done by Ramsay.
II. The average net force exerted by Jon is the same with Ramsay.
III. The work done by both Jon and Ramsay is 12.0 J
A. I and II only
C. III only
D. I, II and III
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Physics 71
10. Pinatacolada.
In a festival, a 3.00 kg pinata full of money was initially hung 1.00 m from
the ground. To make the game more challenging, the pinata was raised to 3.29 m above the
ground. What is the change in the gravitational potential energy of the pinata?
A. +134.9 J
C. 134.9 J
B. +67.3 J
D. 67.3 J
p
A. 2gR
C. gR/2
p
B. 4gR
D. gR/4
12. Liberated Force. Which of the following statements is/are TRUE about the work done by
a conservative force?
I. It is reversible.
II. It is path-dependent.
III. It is equivalent to the change in potential energy.
A. I only
C. I and III
B. II only
D. I, II and III
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13. Elastic Man. Consider a wooden block with mass of 0.50 kg located on a frictionless
surface and connected to an ideal spring whose force constant is 2.0 102 N/m. You
applied a constant force starting at a point where the displacement is highest as shown in
the figure. When the object is located at x = 0.25 m, its speed is equal to v = 10. m/s.
What is the work done by the constant force F?
A. 25.0 J
B. 31.3 J
C. 56.3 J
D. 6.25 J
C. +1.50 J
B. 1.50 J
D. +1.96 J
15. Springiness. A block of mass 2.00 kg with a speed of 6.00 m/s moves towards an uncompressed spring with a force constant of 900. N/m. Which of the following statements is/are
TRUE regarding this scenario?
I. The maximum distance that the spring will be compressed is 0.283 m
II. When the spring is compressed by 0.250 m, the blocks speed is 2.50 m/s
A. I only
B. II only
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Physics 71
C. 1.02 m
B. 0.820 m
D. 1.22 m
17. Direksyon. A particle moving along the x-axis is subject to the potential energy as shown
in the figure. Which of the following statements best describes the motion of the particle
at point S?
A. The particle is moving to the x direction.
B. The particle is moving to the +x direction.
C. The particle has an acceleration in the x direction.
D. The particle has an acceleration in the +x direction.
18. Running cat. A 10.0-kg cat is running at 0.500 m/s while accelerating at a rate of 0.200 m/s2 .
What is the cats linear momentum?
A. 2.00 kg m/s
C. 5.00 kg m/s
B. 3.00 kg m/s
D. 7.00 kg m/s
19. Impulse of the North. A Wildling applied a constant net force of 11.0 N on a spear from
t = 0.400 s to 0.700 s. What is the impulse on the spear due to the Wildling from this time
duration?
A. 3.30 N s
B. 4.40 N s
A6
C. 7.70 N s
D. 11.5 N s
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Physics 71
For the next two items, consider the potential energy diagram shown below.
20. Ux-to-Fx. Which of the following plots best describes the force corresponding to the
potential energy function from x = 0 up to x = x1 ?
21. Equipoints. Which of the following statement is TRUE about the equilibrium points in
the plot?
I. Points K, M and N are stable equilibrium points
II. Point L is an unstable equilibrium point
III. Point N is a neutral equilibrium point
A. I, II and III
C. III only
B. II only
22. Bola sa Pader. A 0.300-kg ball hit a wall at 20.0 m/s causing it to reverse direction and
move at 15.0 m/s. What is the magnitude of the impulse imparted by the wall on the ball?
A. 1.50 kg m/s
C. 6.00 kg m/s
B. 4.50 kg m/s
D. 10.5 kg m/s
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23. Be careful! Consider an isolated system made up of 2 particles, with the one particle
having momentum of P1i = P1xi i + P1yi j and the other particle with momentum of P2i =
P2xi i+ P2yi j. Which of the following statements is TRUE if the external force experienced
by the system is zero?
A. P1xi + P2xi = constant and P1yi + P2yi = constant
B. P1xi + P1yi = constant and P2xi + P2yi = constant
C. P1xi = P2xi and P1yi = P2yi
D. P1xi + P2xi = 0 and P1yi + P2yi = 0
A spring with force constant k is compressed by a distance x from equilibrium with a box with
mass m on one end as shown in the figure. The spring is released and the box moves away
from the spring on a frictionless surface before colliding with another box of mass 2m that is
initially at rest.
24. Inelastic muna. If they stick together after collision, what is the speed of the system?
r
r
x k
x k
C. v =
A. v =
3 m
2 m
r
r
x m
k
B. v =
D. v = 3x
3 k
m
25. Then elastic. If, however, the collision has been elastic, what is the velocity of the object
with mass 2m if the velocity of mass m after the collision is v?
q
q
k
x m v
x mk + v
A.
C.
2
3
q
q
k
x m +v
x mk v
B.
D.
2
3
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26. Talon. A 60.0-kg student is riding on a 100.0-kg cart moving at 10.0 m/s to the right. If the
student suddenly jumped off the left side of the cart with a speed of 2.00 m/s with respect
to the ground, what is the final speed of the cart?
A. 7.20 m/s
B. 14.8 m/s
C. 16.0 m/s
D. 17.2 m/s
27. Sticky Clay Balls. Two clay balls collide at the origin. One ball with mass 2.00 kg has
an initial velocity of 2.00 m/s while the other ball with mass 3.00 kg initially moves at
(2.00 + 3.00 ) m/s. What is the final velocity of the balls if they merge after collision?
A. (+0.400 + 1.80 ) m/s
29. Disk dance. Initially, the marker in a compact disk is at 0 . What is the disks average
angular speed if the marker travelled an angle of 45 after t = 3.50 s?
A. 12.9 rad/s
C. 3.14 rad/s
B. 45.0 rad/s
D. 0.224 rad/s
30. Paikutin mo pa! A disk was spinning counterclockwise about the z-axis at an angular
speed of 20.0 rad/s as it was slowing down at a constant rate. After 5.00 s, it was spinning
clockwise at angular speed was 10.0 rad/s. What is the disks angular acceleration?
A. 6.00 rad/s2 k
B. 2.00 rad/s2 k
C. +2.00 rad/s2 k
D. +6.00 rad/s2 k
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31. Bicycle. A bicycle wheel rotates with an initial angular velocity of 1.50 rad/s at t = 0 s and
a constant angular acceleration of 2.00 rad/s2 . What is the amount of angular displacement
that the bicycle made from t = 1.00 s to t = 3.00 s?
A. 2.50 rad
B. 13.5 rad
C. 11.0 rad
D. 16.0 rad
32. Bentilador. The blade of an electric fan is rotating at 400 rpm. If the blade has a length of
0.400 m measured from the center, what is the tangential speed at the tip of the blade?
A. 2.67 m/s
B. 16.8 m/s
C. 41.9 m/s
D. 160. m/s
33. Wheeeel. A wheel accelerates at a rate of 2.00 m/s2 . At a certain time, the tangential
velocity at the highest point of the wheel is 1.50 m/s. If the radius of the wheel is 0.500 m,
what is the magnitude of the net acceleration at the highest point of the wheel?
A. 2.00 m/s2
B. 2.55 m/s2
C. 4.50 m/s2
D. 4.92 m/s2
34. Bilisan mo pa! A disk with radius 0.100 m is initially at rest and starts to spin while
accelerating at a rate of 2.00 rad/s2 . What is the magnitude of the linear acceleration at the
edge of the disk after 0.800 s?
A. 0.106 m/s2
B. 0.200 m/s2
C. 0.256 m/s2
D. 0.325 m/s2
35. Baton. A baton was made using two balls, each of mass m, connected by a massless rod of
length L. What is the kinetic energy of the baton if it rotates at a constant angular velocity
about an axis passing through the center of the rod as shown in the figure?
A. mL2 2
C. 2mL2 2
B. mL2 2 /4
D. mL2 2 /2
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C. 188 kg m2
B. 13.0 kg m2
D. 253 kg m2
37. Stick Pendulum. A stick is held in a horizontal location. It was allowed to rotate by releasing it from rest,
with pivot point located at a distance one-third its length
L. What is the angular speed when it reaches its vertical
1
2
position? Note:
r Istick (cm) = 12 M L
g
A. 3
L
r
3g
B.
L
r
g
C.
3L
r
g
D.
L
B. 0k
C. 10k
C. +97.4 N m
B. 97.4 N m
D. 56.3 N m
A 11
D. 12k
Midyear 2016
A 12
Physics 71