1- Work is the product of:
a) Force and distance
b) Force and velocity
c) Force and displacement
d) Force and energy
2- A force F acts on a body at an angle of 60
degrees to the horizontal and moves it 10 m. The effective component of the
force which performs work is:
a) 0.5
F
b) 0.866 F
c) F cos 0
d) None of these
3- Work is negative when the angle between the
force and the displacement is:
90 degrees
0 degrees
45 degrees
Between
90 and 180 degrees
4- If the angle between force and displacement is
180 degrees, the work done will be: [ECAT 2012]
Positive
Negative
Zero
All of the above
5- When a bucket is lowered into the well from the surface to some depth, the work done by balancing force is: [ECAT 2015]
Positive
Negative
Zero
Infinity
6- A body of mass 2 kg is being rotated by a 0.5m
long string, work done by the centripetal force is:
Zero
100 J
10 J
20 J
7- If a body of mass 10 kg is raised vertically
through 2 m, then work done is:
19.6 J
196
J
20 J
None of these
8- The work done in the gravitational field is
independent of:
The applied force
The
path followed
Force of gravity
All of these
9- A brick 10 cm thick and of mass 10 kg is raised
and placed on a brick of the same size. The work done is:
88 J
988 J
0.88 J
9.8
J
10- A man pushes a lawn mower through 10 m by a
force of 40N at some angle with the horizontal. If work done by the man is 200
J, the angle is:
20 degrees
30 degrees
45 degrees
60
degrees
11- For which of the following force the work done
is always negative:
Frictional
force
Gravitational force
Both a and b
None of these
12- The force
which does no work on the body on which it acts is:
Elastic force
Centripetal
force
Friction
Gravitational force
13- The work done in
taking a particle from the floor to the table depends upon:
The
path taken
Time is taken for work
Speed
of the particle
14- A man holding 10 N weight moves 7 m
horizontally and 5 m vertically. Find the work done by the man:
70 J
105 J
35
J
All of these
15- The field in
which work done along a closed path is zero is called:
Gravitational
field
Electric
field
Conservative field
Magnetic
field
16- If a body of
weight "W" is lifted through a height "h" then the work
done by man will be:
-Wh
Wh
Wh Sin 0
Zero
17- In a conservative
field, work done in moving a body from one place to the other depends upon the:
Path
fallowed
Initial and final positions
Medium
None
of the above
18- Which one is the non-conservative force:
Frictional force
Tension in the
string
Propulsion force
of a rocket
All of these
19- In the gravitational field if displacement is
in the direction of gravitational force, then work done will be:
Positive
Negative
Zero
Infinity
20- In the gravitational field if displacement is
against the gravitational force, then the work done will be:
Positive
Negative
Zero
Infinity
21- In the gravitational field if displacement is
perpendicular to the gravitational force, then work done is:
Positive
Negative
Zero
Infinity
22- Kilowatt-hour is the unit of:
Electrical energy
Power
Density
Viscosity
23- A 1000 kg truck carrying a load of 500 kg
travels on a mountain road for 5 min at a constant speed. Its power output is
2500 W. Assuming (g = 10 ms-2) it will achieve a vertical height: ECAT
[2014]
75 m
50 m
25 m
100m
24- SI unit of power is:
Watt
Pascal
Newton
Joule
25- The commercial electricity unit is:
Kilowatt
Kilowatt-hour
Horsepower
746 watt
26- The power required to pump 3 kg of water up 10
m in 5 s is:
9800 watt
980 watt
58.8 watt
9.8 watt
27- The power of electric iron is 1KW. The energy
will be consumed at the rate of:
500 J/s
1000 J/s
100 J/s
10 J/s
28- The power needed to lift a mass of 10 kg to a
height of 1 m in 2 sec is:
0 W
20 W
49 W
90 W
29- A machine lifts a mass of 200 kg vertically
upward up to 30 m in 50 sec, its power will be:
12 kW
1.2 kW
6 kW
300 kW
30- A horse pulls a cart with a force of 100 N at
9 km/h. The power exerted by the horse is:
2.5 watt
25 watt
250 watt
900 watt
31- The rate of doing work is called:
Energy
Momentum
Power
Instantaneous work
32- Power is:
Vector quantity
Scalar
quantity
Fundamental quantity
Neither vector nor scalar
33- The momentum
of the body is numerically equal to its kinetic energy at the speed of:
20 m/s
2
m/s
8 m/s
10 m/s
34- When a spring is compressed, it possesses:
E.P.E
G.P.E
K.E
Sound
35- According to the work-energy principle, work done
on a body is equal:
Change in K.E
Change in P.E
Change in G.P.E
All of these
36- K.E of a body is increased by 21%. The
increase in momentum will be:
[ECAT 2012]
5%
10%
30%
21%
37- 1 Cal = ___ J [ECAT 2010]
418
400
10
4.18
38- The gravitational P.E is always determined
relative to:
Some arbitrary position
Height
Earth's surface
Infinity
39- S.I unit of energy is:
Kilo joule
Joule
Watt
Kilowatt
40- The kinetic energy of a body depends upon:
Mass
Velocity
Both
None
41- If the linear momentum of the body measures 50%.
Then the K.E of the body will be increased: [ECAT 2008]
50 %
100 %
125 %
200 %
42- When
mass and speed are doubled at a time, the kinetic energy increases:
2 times
4 times
8 times
16 times
43- A body
of mass 2kg moving with a velocity of 4ms-1 has k>e equal to:
4 J
12 J
16 J
8 J
44- A body
of mass of 1 kg possesses 50 J kinetic energy. What is the speed of the body?
20 ms-1
10 ms-1
50 ms-1
100 ms-1
45- A body at
rest can have:
Energy
Momentum
Velocity
All of the above
46- Two bodies have the same kinetic energy. They are
stopped by applying same retarding force. Which body will stop first? [MDCAT]
Lighter one
Heavier one
Both at the same time
Can’t be
predicted
47- When two protons are closed, their:
K.E increases
P.E increases
Both increases
P.E decreases
48- Two objects of masses 3 kg and 2 kg moving with
velocities of 2 m/s and 3 m/s respectively. Their kinetic energies are in the
ratio: [MDCAT]
1:1
2:3
3:2
9:4
49- The momentum of the body is P and kinetic
energy is E. If its momentum becomes '2p'. Its kinetic energy will be: [MDCAT]
2 E
E
4 E
52 E
50- Hot igneous rocks within 10 km of the earth's
surface are:
In molten form
Partially molten
form
Gaseous form
Both (a) and (b)
51- Some energy is lost as solar energy passes
through the atmosphere. It is due to which reason:
Reflection
Absorption
Scattering
All of these
52- Earth receives energy directly from:
Moon
Wind
Sun
Water
53- The original source of energy from tides is:
Earth
Sun
Moon
All of these
54- The layer of rock that holds water is called:
Geyser
Vapor
Heat energy
Aquifer
55- The heat energy extracted from inside the
earth is called:
Heat energy
Bio-energy
Sound and heat
Geothermal energy
56- Geothermal energy is obtained by:
Radioactive decay
The residual heat of
the earth
Compression of
the material
All of these
57- In some places, water beneath the ground that
is in contact with hot rocks comes out to the surface as:
Hot springs
Geysers
Steam vents
All of these
58- Geysers usually occur in:
Volcanic regions
Hot regions
Radioactive
regions
Weak regions
59- Most geysers erupt at:
Regular intervals
Irregular intervals
At constant
intervals
All are possible
60- Biomass is a potential source of:
Non-renewable
energy
Renewable energy
Conventional
source of energy
Both (b) and (c)
61- For cloudy days or nights, electrical energy
can be stored during the sunlight in:
Nickel silicon
batteries
Nickel cadmium batteries
Cadmium boron
batteries
Batteries cannot
be used
62- Cold water passes over the surface of a
collector and is heated up to about:
60^C
70^C
80^C
100^C
63- The gravitational force of the moon gives rise to:
Waves
Pulses
Tides
Winds
64- The time
taken by an engine of power 5kW to lift a mass of 100 kg to a height of 20 m
is:
2 sec
4 sec
8 sec
16 sec
65- If the momentum
of a body increases by 20%, then the increase in its K.E is:
40%
44%
48%
56%
66- Car X is
traveling at half the speed of car Y. Car X has twice the mass of car Y. Which
statement is correct?
Car X has
half K.E of car Y
Car X has one-quarter of K.E of car Y
Car X has twice the K.E of car Y
The two cars have the same K.E
67- An electric
motor 100 W power dries stirrer in a water bath only 80% of the energy supplied
to the motor is used up in the stirring water. The work done on water in one
second is:
100 J
80 J
180 J
145 J
68- When a
vehicle is moving at a constant velocity and a constant engine force is used to
overcome friction, the product of force times velocity is a measure of:
K.E of the vehicle
Work done by the vehicle
The motive power of the vehicle
The inertia of the vehicle
69- Watt is the
unit of:
Power
Power x t
Energy
Both (b)
and (c)
70- A ball of 1
kg is released from a tower, and the K.E in it after 10 m will be:
0.98 J
9.8 J
10 J
98 J
71- The
retarding force required to reduce the velocity of 3 kg mass from 0.75 m/s to
0.25 m/s in 0.02 seconds will be:
100 N
75 N
50 N
25 N
72- Two bodies A
& B of mass 1 kg and 2 kg respectively have the same momentum, which one has
greater K.E?
A
B
Both have the same energy
None
73- Which one of
the following statements is incorrect?
K.E may be
zero, negative or positive
P.E may be zero, negative or positive
Work done may be zero, negative or positive
Power, energy, and work done are scalars
