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Mock 1 - Physics (1-50).pdf solution

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NMAT PHYSICS SIMULATIONS (MOCK 1)
1. Which of the following does not belong to the group?
A. cryogenics
C. solid state physics
B. relativity
D. kinematics
2. What are the factors that determine the speed of a
satellite which moves in a stable orbit around a planet?
(G represents the universal gravitational constant.)
A. Orbital radius of the satellite, mass of the planet, & G
B. Mass of the satellite and G
C. Mass of the satellite, mass of the planet, and G
D. Mass of the planet and G
8. A body thrown vertically up into the air possesses
kinetic energy at the beginning of its flight, but as it rises,
it loses kinetic energy and acquires potential energy with
respect to the level from which it started. Which of the
following is NOT likely to happen?
A. The kinetic energy is minimum at the lowest point of its
flight
B. As it falls, its potential energy is again is transformed to
kinetic energy.
C. The potential energy is maximum at the highest point
of its flight
D. When it reaches the highest point the kinetic energy
was wholly changed to potential energy
3. An 80-kg mountain climber dangling in a crevasse
stretches a 50-m long rope with a cross-sectional area of
0.00008 m2 by 8.0 cm. What is the Young’s modulus of
the rope, in N/m2?
A. 6.25 x 102
C. 6.25 x 1010
24
B. 6.25 x 10
D. 6.25 x 109
4. A pingpong ball and a golf ball are dropped in a vacuum
chamber from the same time. When they have fallen
halfway, they have the same
A. Velocity
C. Acceleration
B. Kinetic energy
D. Potential energy
5. Which graph shows an inversely proportional
relationship?
A.
C.
B.
D.
6. A force of 80 newtons is used to raise a 300-newton
load using a system of pulleys. The load covered a
distance of 1 m for every 5 m of rope pulled through the
system. The system has an efficiency of
A. 12%
C. 60%
B. 48%
D. 75%
7. Which of the following distance versus time graphs
describes an object moving with increasing speed?
A.
C.
B.
D.
9. Bernoulli’s principle states that A1V1=A2V2. Blood flows
from artery A1, whose cross-sectional area is 50μ2, at a
velocity of 30 mm/s to its more peripheral branches, A2, A3,
A4, and A5. If the total cross-sectional area of the
branches is 500 μ2 and each branch has exactly the same
diameter as the other, what is the velocity of the blood in
the branches?
A. 3.0 mm/s
C. 10.0 mm/s
B. 1.0 mm/s
D. 2.0 mm/s
10. Which is true about the wave nature of sound and that
of light?
which can travel even without any medium.
A. Sound waves and light waves are both electromagnetic
waves and do not need any medium to be able to travel.
B. Sound waves and light waves are both longitudinal
waves and both need a medium to travel.
C. Sound waves are electromagnetic waves and can travel
without any medium, while light waves are
electromagnetic waves, which needs a medium to travel.
D. Sound waves are longitudinal waves which need a
medium to travel while light is an electromagnetic wave
11. The speed of sound in air at 200C is 344 m/s. What is
the wavelength of the note produced by a piano key, if it
has a frequency of 10Hz?
A. 68.8 m
B. 137.6 m
C. 860 m
D. 34.40 m
12. At what point in its motion is the kinetic energy of the
pendulum bob maximum? C
13. How many calories of heat are given off when 200
grams of water is cooled from 100˚C to 30˚C?
A. 2,000 cal
C. 14,000 cal
B. 4,000 cal
D. 20,000 cal
1
14. A 1200-watt heater is used for raising the temperature
of 1 liter of water to boiling point. How long will it take for
the water to boil if the initial temperature of water is 20˚C?
(1 cal = 4.19 joules)
A. 28 s
B. 70 s
C. 279 s
D. 349 s
15. If the absolute temperature of a gas is increased four
times and its pressure is doubled, then the volume will
A. Increase six times
C. Decrease six times
B. Increase two times
D. Decrease two times
16. A glass flask which is partly filled with water is heated
over a Bunsen flame. As soon as the water begins to boil,
the flask is removed from the flame and tightly stoppered
immediately. Boiling stops. When cold water is poured in
the surface of the flask, which of the following will happen
to the water inside the flask?
A. It will begin to boil again since the contraction of the
flask reduces the pressure inside.
B. It will begin to boil again since the condensation of the
steam reduces the pressure inside.
C. It will not boil since the temperature is less than 100˚C.
D. It will not boil since the contraction of the flask
increases the pressure inside.
23. If a horse pulls on a calesa at rest, the calesa pulls
back equally as much on the horse. Will the calesa be set
into motion?
A. No, because the forces cancel each other
B. Yes, because there is a net force acting on the calesa.
C. Yes, because there is a time delay between action and
reaction
D. Yes, because the horse’s pull on the calesa is larger
than the calesa ’s pull on the horse.
24. The range limit of human hearing is 20Hz – 20kHz. If
the speed of sound is 345 m/s, what is the lowest
wavelength possible for human hearing?
A. 17.25 mm B. 17.25 cm C. 17.25 dm D. 17.25 m
25. A capacitor acquires 0.0018 coulomb when 60 volts is
applied. Its capacitance is
A. 0.3 microfarad
C. 30.0 microfarad
B. 3.0 microfarad
D. 300.0 microfarad
26. At what angle between two vectors will the magnitude
of the resultant of the two vectors be minimum?
A. 0˚
C. 90˚
B. 45˚
D. 180˚
17. A Carnot refrigerator takes heat from water at 0˚C
and rejects heat to a room at 27˚C. if 50 kg of water at
0˚C is converted to ice at 0˚C, how much energy must be
supplied to the refrigerator?
A. 4.60 × 10-4 kwh
C. 4.00 × 10-5 kwh
B. 3.90 × 10-4 kwh
D. 2.62 × 10-5 kwh
27. Electroplating results in a better quality product by
applying a relatively
A. Strong current for a shorter time
B. Strong current for a longer time
C. Moderate current for a shorter time
D. Moderate current for a longer time
18. Orange light has a wavelength of 6 x 10-7 m. What is
the frequency? The speed of light is 3 x 108 m/s.
A. 2 x 1015 Hz
C. 5 x 1014 Hz
-15
B. 2 x 10 Hz
D. 5 x 10-14 Hz
28. Which of the following is true when the magnetic flux
through a coil at 200 turns is reduced from 0.25 weber to
0 weber in 0.2 second?
A. The emf is 250 volts.
B. The induced emf in the coil is 220 volts.
C. The emf is 220 volts.
D. The induced emf in the coil is 250 volts.
19. The immediate source of water which forms dew on
grass on a summer morning is the
A. Air
B. Soil
C. Grass
D. Cloud
20. A car travels in a circle at constant speed. Which of
the following is TRUE about the net force on the car?
A. zero because the car is not accelerating
B. directed towards the direction of travel
C. directed towards the center of the circle
D. none of the above
21. A metal cube is heated in Bunsen flame and then
dropped into an insulated beaker containing water. The
masses of the water, the beaker, and the cube, the initial
and the final temperatures of the water, and the beaker
are known. Without further measurements, which of the
following can be calculated?
A. The density of the cube
B. The specific heat capacity of the cube
C. The thermal conductivity of the cube
D. The specific latent heat of the cube
29. What is the potential difference in an electric circuit
with a total resistance of 25k when a 5 mA current
passes through it?
A. 25 V
B. 50 V
C. 125 V
D. 250 V
30. What is the total resistance in the configuration below?
A. 4 k
B. 5 k
C. 7 k
D. 15 k
22. After a cannon ball has been fired into a frictionless
space, how much force is needed to keep it going?
A. zero, since no force is necessary to keep it going
B. one-half the force with which it was fired
C. twice the force with which it was fired
D. the same amount of force with which it was fired
2
Red
A
Violet
B
C
D
Visible Light
31. In the diagram above, the focal length of the lens is F.
No image will be projected on the screen if a candle is
placed
A. Between F and the lens
C. Beyond 4F
B. At 3F
D. At 2F
32. A lemon is colored yellow because
A. It absorb only yellow light
B. It reflects only yellow light
C. Only yellow light can pass through a yellow lemon
D. Only yellow light actually hits the lemon
33. Which of the following explains the appearance of a
rainbow in the sky after a rainstorm?
A. The white clouds are actually prisms composed of
different colors.
B. Sunlight reflected by the ground separates into different
colors in the sky.
C. Raindrops act as prisms that separate into its
components
D. None of these
34. In which situation is there work done on the system?
A. a basket being lifted
B. a man carrying a bag of content on his shoulder
C. a boy pushing against the wall
D. a weightlifter holding a barbell in the air
38. Compared to the wavelengths of visible lights, the
wavelength of the radiation in A and B are
A. Shorter
B. Longer
C. Just as long
D. Not measurable
39. In which of the following items is the center of gravity
located at a point where there is no mass?
A. tennis racket
C. boomerang
B. billiard ball
D. discus
40. A certain solar cooker is made of a big concave mirror.
To get the greatest amount of reflected sunlight, where
should the food be placed?
A. Above the center of the curvature of the mirror
B. At the center of the curvature of the mirror
C. Between the focus and the center of curvature of the
mirror
D. At the focus of the mirror
41. An alpha particle is the same as
A. 21𝐻
C. 32𝐻𝑒
B. 31𝐻
D. 42𝐻𝑒
35. How many images will be formed if a boy stands in
front of two mirrors standing at a 40˚angle to each other?
A. 5
B. 8
C. 7
D. infinite
42. When a large atom such as U splits into two smaller
atoms, then the combined mass of the products resulting
from the splitting will be
A. One half of the original mass
B. Two times more than the original mass
C. One half more than the original mass
D. The same as the original mass
36. Which of the following result if the number of lines in
a diffraction grating of a given width is decreased?
A. The wavelengths can be diffracted will be shorter
B. The wavelengths that can be diffracted will be longer.
C. The spectrum produced will be narrower.
D. The spectrum produced will be broader.
43. The atomic reaction where
the release of
A. A negative beta particle
B. An alpha particle
C. A beta particle
D. A gamma particle
37. A 10-meter object is placed at a distance of 100
meters in front of a lens whose focal length is 50 meters.
Which of the following describes the image formed?
A. It is 4 meters long and inverted
B. It is 4 meters long and erect.
C. It is 10 meters long and inverted
D. It is 10 meters long and erect.
44. An electron is traveling at 1% the speed of the light.
What is the kinetic energy in joules?
(speed of light = 3 × 108 m/s)
A. 4.000 × 10−18 J
B. 4.098 × 1010 J
C. 4.000 × 1018 J
D. 4.098 × 10−18 J
13
5𝐶
becomes
13
6𝐶
results in
3
45. Based on the figure below, how far is the image from
the mirror?
A. 2.5 cm
B. 5 cm
C. 10 cm
D. 15 cm
46. From the figure above, what type of image will be
formed?
A. Real and upright
C. Virtual and upright
B. Real and inverted
D. Virtual and inverted
47. A metal initially at 1000C is immersed in lukewarm
water. What can be observed from this?
A. The water’s temperature will decrease.
B. The water evolves heat to the metal.
C. The metal cools at a temperature less than 1000C.
D. All of the above
48. Which of the following statement is NOT true of
protons and electrons?
A. The positive charge in an atomic nucleus is due to the
protons it contains
B. All protons have the same charge
C. Protons and electrons have charges equal in magnitude
although opposite in sign
D. Protons and electrons have equal masses
49. The radiation from a sample of Krypton-85 decrease to
one-fourth of the original intensity Io in a period of 18
years. What would be the intensity after 18 more years?
A. Io
B.
1
Io
3
235
92𝑈
+ 10𝑛 →
140
54𝑋𝑒
+
92
38𝑆𝑟
C.
1
Io
16
D.
1
Io
9
+ (? ) 10𝑛 + 𝑒𝑛𝑒𝑟𝑔𝑦
50. In a 𝑈 235 fission, represented by the equation above,
Xe140 and Sr92 nuclei are produced and energy is released.
How many n is (are) given off in the process?
A. 1
B. 2
C. 3
D. 4
4
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