CHARIS TRAINING AND REVIEW CENTER
PHYSICS REVIEW
PHYSICS REVIEW
MARK JESTER M. JUANITEZ, LPT, MS
1. Which row correctly describes force,
mass and acceleration as vector or scalar
quantities?
force
mass
acceleration
A
scalar
scalar
scalar
B
scalar
vector
scalar
C
vector
scalar
vector
D
vector
vector
vector
C
2. Which of the following is a scalar
quantity?
A. The braking force needed to stop a car.
B. The effort needed to hammer a nail.
C. The heat needed to boil water.
D. The thrust needed to lift a rocket.
C
3. The diagram show the same object on
a smooth table. Four different pairs forces
act on the object. Which pair of forces
causes the greatest acceleration?
C
4. A car starts from rest and is uniformly
accelerated to a speed of 30 m/s in 6 s.
What is the distance travelled by the
car?
A. 5 m
B. 30 m
C. 90 m
D. 180 m
C
Formula & Solution
2
d=Vit + ½ at
2
d= (0)(6) + ½ (30-0/6) 6
d= 90 m
5. A truck takes 20 s to travel the first 80
m and another 10 s to travel a further
70 m. What is the average speed?
A. 0.2 m/s
B. 2.3 m/s
C. 4.0 m/s
D. 5.0 m/s
D
Formula & Solution
Vave= total distance/total time
Vave= (80m+70m)/ (20s+10s)
Vave= 5.0 m/s
6. What must be changed when a
body is accelerating?
A. The force acting on the body.
B. The mass of the body.
C. The speed of the body.
D. The velocity of the body.
D
7. A car driver takes a total of two hours to make a
journey of 75 km. She has a coffee break of half
an hour and spends a quarter of an hour
stationary in a traffic jam. At what average speed
must she travel during the rest of the time if she
wants to complete the journey in the two hours?
A. 38 km/hr
B. 50 km/ hr
C. 60 km/hr
D. 75 km/hr
C
Formula & Solution
v= d/t
v= 75 km/ 1.25hrs
v= 60km/hr
8. Which sequence represents, in the correct order, the
transformation of the gravitational potential energy after the ball
is released over the edge of the balcony, falls on to a concrete
path and bounces back up?
A. >elastic potential energy>kinetic energy> chemical potential
energy
B. >elastics potential energy>kinetic energy>elastic potential
energy
C. >kinetic energy> elastic potential energy> kinetic energy
D. >kinetic energy> gravitational potential energy> elastic
potential energy
A
9. A car of mass 800 kg is being driven along a level
road. The engine supplies a forward force of 3600 N
and the total resistive force is 2000 N. What is the
acceleration of the car?
A. 2.0 m/s^2
B. 2.5 m/s^2
C.4.5 m/s^2
D. 7.0 m/s^2
A
Formula & Solution
a= Fnet/m
a= (3600N- 2000N)/ 800kg
2
a= 2.0 m/s
10. A lump of stone is weighed using spring balance
and a pan balance. This experiment is repeated on
the moon. Are the readings for each balance the
same or different when taken on Earth and on the
Moon?
B
11. Nine bags of flour, each of mass 1.5 kg,
fills an empty box that measures 0.30 m x
0.24 m x 0.24 m with a mass of 0.5 kg. What
is the average density of the full box?
A. 187.5 kg/m^3
B. 194.4 kg/m^3
C. 781.3 kg/m^3
D. 810.2 kg/m^3
D
Formula & Solution
density= mass/ volume
3
density= 14kg/0.01728 m
3
density= 810.2 kg/ m
12. A scientist weighs a fish using two spring
balances. The spring balance read
80 N and 20 N. What is the weight of the
fish?
A. 60 N
B. 80 N
C. 100 N
D. 200 N
C
Formula & Solution
Fnet or W= F1 + F2
W= 80 N + 20 N
Wfish= 100 N
13. Which statement about gravitational fields is
correct?
A. Gravitational fields cause forces on objects
because they are charged.
B. Only planets and stars have gravitational fields.
C. The gravitational field of the Earth acts inwards
towards the center of the Earth.
D. The gravitational field strength on the Moon is
less than on the Earth because there is no
atmosphere on the Moon.
C
14. A girl uses paper-clips to balance a toy bird on
her finger. What is the effect of the paper-clips
hanged at the end part of the bird’s wing?
A. They help to raise the center of gravity above
the finger.
B. They help to raise the center of gravity to her
finger.
C. They help to lower the center of gravity below
her finger.
D. They don’t affect the center of gravity.
C
15. The height of a mercury barometer is h when
the atmospheric pressure is 100 000 Pa. What is the
pressure at point X (where h/5)?
A. 20 000 Pa
B. 80 000 Pa
C. 120 000 Pa
D. 180 000 Pa
B
Formula & Solution
1/5 * 100 000 Pa=20000 Pa
Px= 100 000 Pa- 20 000 Pa
Px= 80 000 Pa
16. The height of the column mercury in a mercury
barometer on a particular day is measured at 75
cm. What is the value of the atmospheric
pressure? (density of mercury= 13 600 kg/m^3; g=
10N/kg)
A. 1 810 Pa
B. 10 200 Pa
C. 102 000 Pa
D. 181 000 Pa
C
Formula & Solution
Pa = ρ g h
Pa= (13600) (10) (0.75)
Pa= 102 000 Pa
17. A boy is trapped in a large area of very soft
mud. A man rescues the boy by crawling across a
long, light board rather than by walking into the
mud. What effect, if any , does the board have on
the force and pressure on the mud, compared
with walking?
C
18. A person exerts a horizontal force of
500 N on a box which also experiences a
friction force of 100 N. How much work is
done against a friction when the box moves
a horizontal distance of 3 m ?
A. 300 J
B. 1 200 J
C. 1 500 J
D. 1 800 J
B
Formula & Solution
W= Fnet * d
W= (500N-100N) * 3 m
W= 1 200 J
19. A girl of weight 500 N runs up a
flight of stairs in 10 s. The vertical height
of the stairs is 5 m. What is the average
power developed by the girl?
A.50 W
B. 100 W
C. 250 W
D. 1 000 W
C
Formula & Solution
P= W/t
P = F*d/t
P= (500N* 5m)/ 10s
P= 250 W
20. Which line in the table describes
the movement of particles in copper
and in air at 20 degree Celsius?
C
21. Some oxygen gas is in a sealed container that
has a constant volume. What will happen to the
oxygen molecules when the gas is heated?
A. They will expand.
B. They will move more quickly.
C. They will move further apart.
D. They will become denser.
B
22. Three blocks, at temperatures T1, T2
and T3, are in good thermal contact.
At which temperatures (0C) are the
blocks in thermal equilibrium?
B
23. Which of the following expands most
when its temperature is raised to 10 K?
A. 10 cm^3 of air
B. 10 cm^3 of copper
C. 10 cm^3 of ice
D. 10 cm^3 of water
A
24. The temperature shown by a mercury-inglass thermometer increases. Which of the
following is constant?
A. The density of the mercury.
B. The internal energy of the mercury.
C. The mass of the mercury.
D. The volume of the mercury.
C
25. Which line in the table correctly
shows examples of transverse and
longitudinal waves?
A
26. The dipper in a ripple tank vibrates
at a frequency of 4.0 Hz. The distance
between the two crests is 20 cm. What
is the speed of the wave?
A. 40 cm/s
B. 80 cm/s
C. 120 cm/s
D. 200 cm/s
B
Formula & Solution
v= f λ
v= (4Hz) (20cm)
v= 80 cm/s
27. Which may be used to calculate the
wavelength of a wave?
A. The frequency divided by the wave
speed.
B. The frequency divided by the period.
C. The wave speed multiplied by the
frequency.
D. The wave speed multiplied by the period.
D
v= f λ
λ= v/f
(since f= 1/T), then
λ= v/(1/T)
λ= v* T
28. Which type of electromagnetic
radiation travels at the highest speed
through a vacuum?
A. Gamma rays
B. Light waves
C. Radio waves
D. None-all have the same speed
D
29. A sonic “tape measure” is used to measure the
length of the room. It measures a time interval of
0.060 s between a transmitting sound pulse and
receiving the echo. The speed of sound in air is
330 m/s. How far is the reflecting wall from the
tape measure?
A. 5.5 m
B. 9.9 m
C. 11 m
D. 20 m
B
Formula & Solution
d= v/t
d= (330 m/s) ( 0.030s)
d= 9.9 m
30.What is the approximate range of
audible frequencies for a young
person?
A. 1 Hz- 20 Hz
B. 20 Hz- 20 kHz
C. 20 kHz- 200 kHz
D. 1000 kHz- 20 000 kHz
B
31. A child plays a note on a trumpet. She
then plays a louder note of higher pitch.
How do the amplitude and frequency of
the second sound compared with the first?
A
32. Which of the following changes to
a wire when resistance is doubled?
D
R= ρL/A
ρL= RA
(R is inverse proportional to A)
33. Two 3-ohm resistor are connected in a
series circuit. The ammeter reading is 2 A.
What is the current at a point in between
two resistors?
A. 1 A
B. 2 A
C. 3 A
D4A
B
IT= I1 =I2= I3
*Total I is constant in series ckt.
34. A 5-ohm resistor connected to a
cell of e.m.f of 2 V. How much heat
energy is produced in the resistor in 6
seconds.
A. 2.5 J
B. 4.8 J
C. 10 J
D. 60 J
B
Formula & Solution
2
E= Pt where P= V /R
2
E= (V /R) * t
2
E= (2 /5) * 6
E= 4.8 J
35. The cost of a unit (kWh) of electricity is 10
cents. What is the total cost when all these
appliances are used for the times shown below?
A. 6.5 cents
B. 65 cents
B
C. 265 cents
D. 5060 cents
Formula & Solution
E= Pt
Elamp= 0.1kW * 5hrs= 0.5kWh
Eheater= 1.5kW *3hrs = 4.5kWh
Ecooker= 3.0 kW * 0.5hr= 1.5kWh
Cost= Etotal* Rate
Cost= 6.5 kWh * 10 cents
Cost=65 cents
36. Which car moving from rest has an
average acceleration of 5 m/s^2?
A. car reaching a speed of 10 m/s in 2 s
B. car reaching speed of 20 m/s in 2 s
C. car reaching speed of 40 m/s in 2 s
D. car reaching speed of 60 m/s in 2s
A
37. A horizontal line in a speed-time
graph describes an object that is?
A. at rest
B. moving at constant speed
C. accelerating
D. cannot be determined
B
38. A car heading East is acted by four forces: P
(air resistance), Q (thrust),
R (weight), S (friction). Which force or forces, when
increased in value, would cause an increase in
speed?
A. P and S
B. Q only
C. R only
D. R and Q
B
39. Which quantity is calculated by
multiplying the magnitude of a force
by the distance moved in the direction
of the force?
A. work
B. pressure
C. power
D. acceleration
A
40. A brick (L=10 cm, W=5 cm, H= 20
cm) with a weight of 80 N stands
upright on the ground. What is the
pressure it exerts on the ground?
A. 0.4 N/cm^2
B. 2.5 N/cm^2
C
C.1.6 N/cm^2
D. 0.63 N/cm^2
Formula & Solution
P= F/A
P= 80 N/ (10cm*5cm)
2
P= 1.6 N/cm
41. A spring is shaken from side to side to
produce a wave. If the distance between
two successive peaks is 0.60 m and the
frequency is 2.5 Hz, how long does it take for
a wave to travel 3.0 m along the spring?
A. 0.20 s
B. 0.50 s
C. 2.0 s
D. 5.0 s
C
Formula & Solution
t= d/ v where v= f λ
t= d / f λ
t= 3m / (2.5Hz* 0.60m)
t= 2.0 s
42. Charge Q is a fundamental unit of
electricity. Its unit is?
A. Coulomb (C)
B. Ampere. Second (A.s)
C. Joule/Volt (J/V)
D. All of the above
D
I= Q/t
Q= It
C= A.s ( Ampere.second)
V= W/Q
Q= W/V
C= J/V (Joule/Volt)
43. An elementary particle with negative
charge is?
A. proton
B. electron
C. neutron
D. quartz
B
44. Based on the equation E=mc^2, where c is the
speed of light, what can be inferred on the
amount of energy possessed by the object?
A. The energy is directly proportional to the mass
of the object.
B. The energy is inversely proportional to the mass
of the object.
C. The energy does not depend on the mass of
the object.
D. The energy is twice greater than the mass of
the object.
A
45. Why does pencil appear broken at the
boundary between air and water as viewed
from the side of a glass of water?
A. The speed of light in air and in water is
not affected when it passes the glass.
B. The speed of light in air and in water is the
same.
C. Light travels slower in air than in water.
D. Light travels faster in air than in water.
D
46. Which of the following describes the
transformation of energy in an electric
motor?
A. Mechanical energy > Electrical energy
B. Electrical energy > Mechanical Energy
C. Chemical energy > Mechanical energy
D. Chemical energy > Electrical Energy
B
47. At which location does the
skateboarder have the most kinetic
energy and the least potential energy?
A. Location 1
B. Location 2
C. Location 3
D. Location 4
B
48. Which description is TRUE about the radio
waves in the spectrum?
A. It has the shortest wavelength and highest
frequency.
B. It has the longest wavelength and lowest
frequency.
C. It has the longest wavelength and higher
frequency.
D. It has the shorter wavelength and lower
frequency.
B
RMIVUXG
longest λ - shortest λ
lowest f - highest f
49. If the path is a straight line, what is
the total displacement when object
returns to its starting position?
A. 0 m
B. 30 m
C. 50 m
D. 100 m
A
50. Which of the following is true about an object
that travels 5 meters to the left, then 2 meters up,
then another 5 meters right?
A. The displacement of the object is equal to 12
meters.
B. The displacement of the object is equal to 12
meters down.
C. The total distance travelled by the object is
equal to 12 meters.
D. The total distance travelled by the object is
equal to 12 meters down.
C
51.Which of the following is TRUE about
electromagnetic waves?
A. They are transverse waves.
B. They can travel without medium.
C. They are produced by moving
charges.
D. All of the above
D
52. A 1000 kg car starts at rest and after
8 seconds it is moving at 130 m/s. What
is the net force of the car at t = 8 secs?
A. 14 650 N
B. 16 250 N
C. 18 220 N
D. 20 250 N
B
Formula & Solution
F= ma
where a= vf-vi / t
F= (1000) (130-0/ 8)
F= 16 250 N
53. You travel to a city 100 km away in
4.5 hours. What is your instantaneous
speed in km/hr at the red light?
A. 0 km/hr
B. 80 km/hr
C. 180 km/hr
D. 500 km/hr
A
54. What is the potential energy of the box
whose mass is 1 kg raised to an elevation of
2.5 m? (Use g=9.8 m/s^2)
A. 12. 5 J
B. 24. 5 J
C. 36. 5 J
D. 48. 5 J
B
Formula & Solution
PE= mgh
2
PE= 1kg (9.8m/s ) (2.5m)
PE= 24.5 J
55. What is the new kinetic energy of an
object if both of its mass and velocity are
doubled?
A. KE is halved.
B. KE is quartered.
C. KE is doubled.
D. KE is 8 times greater.
D
Formula & Solution
2
KE= 0.5 mv
2
KEi= 0.5 (1) (1) = 0.5 J
2
KEf = 0.5 (2) (2) = 4 J
KEf / KEi = 4/0.5= 8
56. Sound wave can travel to the
following medium except?
A. metal
B. sea water
C. air
D. vacuum
D
57. Which of the following statements is NOT
true about kinetic energy?
A. If two objects have the same mass then
the one that is slower has greater kinetic
energy.
B. Free falling objects have increasing
kinetic energy.
C. Kinetic energy is always positive.
D. Kinetic energy is expressed in Joules.
A
58. The y-component of a 5-N force
applied 65-degree North East is? (cos
65=0.42, sin 65= 0.91)
A. 2.00 N
B. 3.00 N
C. 4.55 N
D. 6. 66 N
C
Formula & Solution
o
Fy = Fa sin 65
Fy = 5 (0.91)
Fy = 4.55 N
59. The gravitational force of two
identical mass (m= 10 kg) separated by
half a meter is? (Use G= 6.7 x 10-11
Nm^2/kg^2)
A. 1.28 x 10-8 N
B. 2.68 x 10-8 N
C. 4. 28 x 10-8 N
D. 6. 00 x 10-8 N
B
Formula & Solution
2
Fg =Gm1m2/ r
-11
2
Fg = (6.7x10 ) (10*10) / (0.5)
-8
Fg = 2.68 x 10 N
60. What happens to the momentum of a
delivery truck if its speed is three times
greater than its original value?
A. Stays the same
B. Halved
C. Tripled
D. Doubled
C
61. The magnitude of the force
needed to maintain a 100-ton object
to move at 4 m/s is __________.
A. 4 N
B. 10 N
C. 0 N
D. 7 N
C
62. The centripetal acceleration of an
object moving at 6 m/s in a circular
path (r = 1.5m) is?
A. 24 m/s^2
B. 44 m/s^2
C. 64 m/s^2
D. 84 m/s^2
A
Formula & Solution
2
ac = v / r
2
ac = (6 m/s) / 1.5m
2
ac = 24 m/s
63. What happens to the centripetal
force F if the linear velocity is halved
but the radius is doubled?
A. F = 1/2 Fo
B. F = 1/3 Fo
C. F = 1/6 Fo
D. F = 1/8 Fo
D
Let the original force F0= 1 N
2
Fc =m v / r
2
Fc = (1) (0.5) / 2
Fc= 0.125 or 1/8 Fo
64. Which of the following is a physical
quantity that has a magnitude and
direction?
A. Vector
B. Frame of reference
C. Resultant
D. Scalar
A
65. The following are vector quantities
except?
A. weight
B. momentum
C. volume
D. electromagnetic fields
C
66. If the graph of the displacement vs.
time of a particle is plotted, the slope
will give the particle’s
A. kinetic energy
B. speed
C. momentum
D. velocity
D
67. The power output of a light bulb is 3 W.
How much energy does the lamp give out
in 60 s?
A. 3 J
B. 12 J
C. 120 J
D. 180 J
D
Formula & Solution
E=Pt
E= (3W) (60s)
E= 180 J
68. A 4.0 kg mass of copper is heated for 40
s by a heater that produces 50 J/s. The
specific heat capacity is 300 J/kg. K. What is
the rise in temperature?
A. 1.7 K
B. 2.0 K
C. 3.2 K
D. 5.0 K
A
Formula & Solution
Q= mcΔT where Q= Pt
Pt= mcΔT
(50) (40) = (4) (300) ΔT
ΔT = 1.7 K
69. Which of the following is a correct
example of a longitudinal wave?
A. Gamma
B. Radio Wave
C. Sound wave
D. X-ray
C
70. The action of distorting an image
by viewing through a medium is?
A. reflection
B. polarization
C. refraction
D. total internal reflection
C
71. Which type of electromagnetic
radiation travels at the slowest speed
through a vacuum?
A. X-ray
B. Light Waves
C. Microwave
D. None of the above
D
72. Which set of information about
gamma ray is correct?
A
73. What is the magnetomotive force
in a 100-turn coil of wire with 2.5 A
flowing through it?
A. 100 At
B. 250 At
C. 275 At
D. 352 At
B
Formula & Solution
mmf= I.t
mmf= (2.5A) (100 turns)
mmf= 250 A.t
74. How much energy is transformed in the
conductor when 50 C of charge flows
through it and the voltage between two
ends of the conductor is 6 V?
A. 0.12 J
B. 8.33 J
C. 56 J
D. 300 J
D
Formula & Solution
V= W/q since W=E
E= Vq
E= (6V) (50C)
E= 300 J
75. How much work is needed to move
a charge of 0.5 C from point x to y if
the potential difference existing
between two points is 3.5 V?
A. 0.14 J
B. 1.75 J
C. 4.50 J
D. 7. 00 J
B
Formula & Solution
V= W/q
W= Vq
W= (3.5V) (0.5C)
W= 1.75 J
76. What is the resistivity of the given
material whose resistance is 2 ohms; area of
cross-sectional area is 25 cm^2 and length
of 15 cm?
A. 1.1 ohms
B. 2.2 ohms
C. 3.3 ohms
D. 4.4 ohms
C
Formula & Solution
R= ρL/A
ρ=RA/ L
ρ= (2) (25) / 15
ρ= 3.3 ohm-cm
77. A 5.0 Ω resistor and 10.0 Ω resistor
are connected in series across a 12 V
D.C supply. What is the current in the
circuit?
A. 0.2 A
B. 0.6 A
C. 0.8 A
D. 12 A
C
Formula & Solution
R= V/I
Itotal= Vtotal / Rtotal
Itotal = 12V/ 15 Ω
Itotal = 0.8 A
78. A 1.5 C charge experiences a force
of 3.0 N. The magnitude of the electric
field is?
A. 1.0 N/C
B. 1.5 N/C
C. 2.0 N/C
D. 2.5 N/C
C
Formula & Solution
E= F/Q
E= 3.0 N / 1.5 C
E= 2.0 N/C
79. A conductor carries a current of 5.0
A. How long does it take for 5.0 C of
charge to pass one point in the
conductor?
A. 1.0 s
B. 5.0 s
C. 12.0 s
D. 25.0 s
A
Formula & Solution
I= q/t
t= q/I
t= 5.0 C / 5.0 A
t= 1.0 s
80. What is the magnetic force on a
2.5-m wire carrying a current of 0.5 A
when the magnetic field is 5 T?
A. 1.25 N
B. 2.25 N
C. 3.50 N
D. 6.25 N
D
Formula & Solution
F= BIL
F= (5T) (0.5A) (2.5m)
F= 6.25 N
81. What will happen when two like
charges are brought together?
A. They will repel each other.
B. They will neutralize each other.
C. They will attract each other.
D. They will have no effect on each
other.
A
82. If you comb your hair and the
comb becomes positively charged,
what will happen to your hair?
A. It will remain un-charged.
B. It will become positively charged.
C. It will be repelled by the comb.
D. It will become negatively charged.
D
83. Which of the following describes
the usual way by which a material can
gain a positive charge?
A. By gaining protons
B. By losing protons
C. By gaining electrons
D. By losing electrons
D
84. ROYGBIV is the basic component of white
light. Which color of light carries the most
energy?
A. Blue
B. Orange
C. Green
D. Red
A
ROYGBV
longest λ - shortest λ
lowest f - highest f
85. Light is an electromagnetic wave. Which
characteristic is common in all electromagnetic
waves?
A. amplitude
B. speed
C. frequency
D. wavelength
B
86. How does the wavelength of infrared (IR)
compare with the wavelength of ultraviolet (UV)
waves?
A. Infrared waves have longer wavelength.
B. Infrared waves have shorter wavelength.
C. IR waves have the same wavelength as the UV
waves.
D. IR is not comparable in wavelength with the UV
waves
A
RMIVUXG
longest λ - shortest λ
lowest f - highest f
87. The figure below shows three pairs of plates.
The electrostatic force between the plates is
shown for two of the pairs. If B is negative, what is
the charge of A? and what kind of force exists in
the third pair?
A. negative, attractive
B. positive, attractive
C. negative, repulsive
D. positive, repulsive
B
88. A cold spoon becomes hot after it
was submerged in a hot congee. The
heat transfer manifested here is?
A. Conduction
B. Radiation
C. Convection
D. None of them
A
89. In a transverse wave, the individual
particles of the medium ______.
A. move in circles
B. move in ellipses
C move parallel to the direction of
travel
D. move perpendicular to the direction
of travel
D
90. Compared to a thin string of the
same length and tightness, a thick
string produces sounds of ____________.
A. the same pitch
B. higher pitch
C. lower pitch
D. lower then higher pitch
C
91. The work done by a friction is?
A. always positive
B. always negative
C. always zero
D. either positive or negative
B
92. A pendulum which is suspended from the
ceiling of a railroad car is observed to hang at
an angle of 10 degrees to the right of vertical.
Which of the following could explain this
phenomenon?
A. The railroad car is at rest.
B. The railroad car is accelerating to the left.
C. The railroad car is moving with constant
velocity to the right
D. The railroad car is accelerating to the right
B
93. For an object in uniform circular
motion, the direction of the
instantaneous acceleration vector is?
A. tangent to the path of the motion
B. equal to zero
C. directly radially inward
D. directed radially outward
C
94. Electric current may be expressed
in which one of the following units?
A. coulomb/volt
B. joules/coulomb
C. coulomb/second
D. ohms/second
C
Formula & Solution
I=q/t
A= C/s
95. If the distance between two
objects, each of mass ‘M’, is tripled ,
the force of attraction between the
two objects is?
A. 1/2 the original force
B. 1/3 the original force
C. 1/9 the original force
D. unchanged
C
Formula & Solution
Let F0= 1N
2
Fg =Gm1m2/ r
2
Fg = 1 / (3)
Fg = 1/9 F0
96. If the resultant force acting on a
body of constant mass is zero, the
body’s momentum is?
A. increasing
B. decreasing
C. always zero
D. constant
D
97. A box is initially at rest on a horizontal ,
frictionless table. If a force of 10 N acts on a
box for 3 seconds, what is the momentum of
the box at the end of the 3-s interval?
A. 3.3 N.s
B. 30 N.s
C. 45 N.s
D. 50 N.s
B
Formula & Solution
p=mv where I= p and I= Ft
p= Ft
p= (10 N) (3s)
p= 30 N.s
98. A ball leaves a girl’s hand with an
upward velocity of 6 m/s. What is the
maximum height of the ball above the girl’s
hand?
A. 1.2 m
B. 1.6 m
C. 1.8 m
D. 2.1 m
C
Formula & Solution
2
2
d= Vf - Vi / 2g
2
2
d= (0) - (6) / -19.6
d= 1.8 m
99. A 10-kilogram body initially moving with a
velocity of 10 m/s makes a head-on collision with
a 15-kilogram body initially at rest. The two objects
stick together. What is the velocity of the
combined system just after the collision?
A. 2 m/s
B. 4 m/s
C. 6 m/s
D. 8 m/s
B
Formula & Solution
m1v1i + m2v2i = (m1 + m2) vf
(10*10) + (15*0) = 25 vf
100 =25 vf
vf= 4 m/s
100. A 2-kg cylinder pulley with radius of 0.1 m
rotates at a constant angular speed of 2
rad/s. What is the angular momentum of the
pulley?
A. 0.01 kg.m^2/s
B. 0.02 kg.m^2/s
C. 0.03 kg.m^2/s
D. 0.04 kg.m^2/s
B
Formula & Solution
2
L= I ω where Icylinder= 0.5 mr
L= I ω
2
L ={(0.5) (2kg) (0.1m) } 2rad/s
2
L= 0.02 kg.m /s
THANK YOU!