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ScribdTranslationsFINAL PHYSICS EXAM
CORRESPONDING TO THE LEVELING COURSE SEMESTER I 2013
Names RATING
Reactvo2
This evaluation consists of 10 topics, each weighted ten points. The use of calculators is prohibited.
cell phones. The evaluation is strictly personal. In case you need to consult the teacher, raise your hand so that the teacher
he/she can assist you. Justify your answer. The procedure can be elaborated with a pencil. The answers must be
selected with pen. Correction fluid is not allowed.
A block A with a mass of 100kg is connected to a weight w as shown in the figure. If there exists a coefficient
with a friction coefficient of 0.3 and the block rises at constant speed, the weight w is:
84 kg-f
b) 104 kg-f
124 kg-f
100 kg-f
c) 36 kg-f
2. A box with mass M = 5 kg slides 10 meters with
constant speed on a rough inclined plane whose
The surface is forming a 30° angle with the horizontal. What is the magnitude of the work done by the
friction?
100 J 50 J c) 320 J d) 105 J e) 245 J
3. A body with weight w is pushed over a horizontal surface with a coefficient of friction µ by a
force F that forms an angle ϴ with the horizontal below the horizontal. What is the value of F for it to be
Does the body move with constant speed? What is the value of the normal?
μw wtanθ
a) :
cosθ−μsinθ tanθ+ μsecθ
μw wsecθ
:
tanθ+ μtanθ sinθ−μsenθ
μw cosθ
c) :
cosθ−μsenθ cosθ−usenth
μw cosθ
d) :
cosθ−μsenθ cosθ−μsenθ
μw wsenθ
e) :
cosθ+ μcosθ sinθ+ μsenθ
4. In the following figure, bodies A and B each weigh 50 kg.f and move at a constant speed. The
The coefficient of friction is 0.2 for both bodies. What is the weight of body C?
38 kg.f
b) 58 kg.f
c) 48 kg.f
18 kg.f
28 kg.f
5. A ball is thrown upward. At a height of 10 meters above the ground, the ball has an energy
potential of 50 J (taking the ground as the reference level) and moves upward with an energy
50 J cinema. The maximum height reached by the ball is close to:
50 m 40 m c) 30 m d) 20 m 10 m
6. For the following graph, what will be the magnitude of the force that needs to be added for the system to be in
balance?
5 kg.f
7 kg.f
c) 4 kg.f
3 kg.f
1 kg.f
A block is launched onto an inclined surface with an initial velocity of 10 m/s as indicated in
the figure. If the coefficient of kinetic friction between the block and the inclined plane is 0.2 then the
maximum height reached by the block is:
7.23 m
b) 6.92 m
c) 3.97 m
0.40 m
0.69 m
8. Calculate the weight of body A in the figure
84 kg.f
63 kg.f
90 kg.f
64 kg.f
50 kg.f
Prepared by: Carlos Portlla Lazo, Eng. 05/08/2013
FINAL PHYSICS EXAM
CORRESPONDING TO THE REMEDIAL COURSE SEMESTER I 2013
9. Which of the following units is a unit of energy?
−1 −1
a) Ws b) Wm c) Ws d) Nms e) N/A
10. A hot air balloon rises with constant speed. The weight of the balloon does work:
positive.
b) zero.
c) negative.
d) It is impossible to carry out
e) data is missing to provide an answer.