| 1 |
The wavelength of light observed on the earth, form a moving star is found todecrease by 0.05%. Relative to the earth the star is |
moving away with a velocity of 1.5 x 10<sup>5</sup>m/s
moving away with a velocity of 1.5 x 10<sup>4</sup>m/s
coming closer with a velocity of 1.5 x 10<sup>5</sup>m/s
<div>coming closer with a velocity of 1.5 x 10<sup>4</sup>m/s</div>
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| 2 |
The frequency of the fundamental mode of open at one organ pipe is 400 Hz. Ifone end of pipe is closed the fundamental frequency will be |
800 Hz
600 Hz
400 Hz
200 Hz
|
| 3 |
A closed organ pipe and an open organ pipe have their first overtone identical infrequency. Their lengths are in ratio |
3:4
1:2
2:3
3:5
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| 4 |
When passes from medium to another, deviate from its path is called |
reflection
<div>refraction</div>
diffraction
transmission
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| 5 |
A whistle is revolved with high speed in a horizontal circle of radius R. to an observer at the centre of the circle the frequency of the whistle will appear to be: |
Decreasing
Increasing
Both
Constant
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| 6 |
The fundamental frequency in a stretched string is 10 Hz. To double the frequency, the tension in it must be changed to:
|
T<sub>2</sub> = 2T<sub>1</sub>
T<sub>2</sub> = 4T<sub>1</sub>
T<sub>2</sub> = T<sub>1</sub>
none of these
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| 7 |
The frequency of an open pipe is f. if one end is closed then its fundamental frequencywill be: |
f/2
3f/4
f
2f
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| 8 |
Where in standing wave, do the vibrations of the medium occur? |
Only at the nodes
Only at the antinodes
At all points between the nodes
At all points between the antinodes
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| 9 |
A sonar depth finder in a boat uses sound signals to determine the depth of water. Fourseconds after the sound leaves the boat it returns to the boat because of reflection fromthe bottom. Assume the speed of sound in water is 1,460 meters per second. The depth of the water is, in meters, : |
2,200
4,800
4,400
2,920
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| 10 |
A string vibrates in 1 loop has frequency 25 Hz if it moves in 2 loops its frequencywould be: |
25 Hz
50 Hz
12.5 Hz
5Hz
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| 11 |
A progressive sound wave is a means of transferring energy. A progressive sound waveof constant frequency is generated in air. The intensity of energy transfer is directlyproportional to another of the wave parameters. Which of the following is correct? |
<div>Intensity 𝖺 (𝑎𝑚𝑝𝑙𝑖𝑡𝑢𝑑𝑒)<sup>2</sup></div>
<div>Intensity 𝖺 (𝑝𝑒𝑟𝑖𝑜𝑑𝑖𝑐 𝑡𝑖𝑚𝑒)<sup>2</sup></div>
<div>Intensity 𝖺 (𝑠𝑝𝑒𝑒𝑑)<sup>2</sup></div>
<div>Intensity 𝖺 (𝑤𝑎𝑣𝑒𝑙𝑒𝑛𝑔𝑡ℎ)<sup>2</sup></div>
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| 12 |
If a transverse wave has a speed of 10 m/ sec and frequency of 10 cycle/ sec itswavelength is: |
1 m
10<sup>-2</sup>
cm
10 m
10 cm
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| 13 |
A point on the rim of a wheel 4m in diameter has a velocity of 1600 cm s-1. The angular velocity of the wheel is |
<div>2 rad s<sup>-1</sup></div>
<div>4 rad s<sup>-1</sup></div>
<div>6 rad s<sup>-1</sup></div>
<div>8 rad s<sup>-1</sup></div>
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| 14 |
A body moving in a circular path with a constant speed has a |
Constant velocity
Constant kinetic energy
Constant acceleration
<div>Constant displacement</div>
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| 15 |
For a particle in uniform circular motion the relation a = r 𝑎 of accelerations hold. The acceleration 'a' |
is centripetal acceleration
Is tangential acceleration
is radical acceleration
both A and B
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| 16 |
A particle is moving with constant speed by keeping itself at constant distance from a fixed point in a given plane. Its motion is |
Circular motion
Uniform circular motion
Uniform circular motion with fixed axis of rotation
Uniform circular motion with axis of rotation not defined
|
| 17 |
In uniform circular motion, the factor that remains constant is |
Linear velocity
Centripetal force
Acceleration
speed
|
| 18 |
The mud flies off the tyre of a fast moving car in the direction |
parallel to the moving tyre
anti parallel to the moving tyre
tangent to the moving tyre
none of these
|
| 19 |
Two artificial satellites of unequal masses are revolving in a circular orbit around the earth with a constant speed. Their time periods: |
Will be different
Will depend on their masses
Will be same
Will depend upon the place of their projection
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| 20 |
The angular momentum changes form 2 units to 6 units in 4s. the torque is |
1 unit
3/2unit
1/2unit
4unit
|
| 21 |
For a body moving with constant speed in a horizontal circle, which of the following remains constant? |
Velocity
Centripetal force
Acceleration
Kinetic energy
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| 22 |
A body is moving in a circle with a constant speed. it has |
a constant velocity
a constant acceleration
a velocity of constant magnitude
an acceleration of constant magnitude
|
| 23 |
If a rotating body is moving counter clockwise, direction of angular velocity will be |
along linear velocity
towards the center
along the axis of rotation
away from center
|
| 24 |
A satellite moving round the earth constitute |
An inertial frame of reference
Non inertial frame
Neither inertial nor non inertial
Both inertial and non-inertial
|
| 25 |
The force which provides the necessary centripetal force to keep the mud in circular path is called |
cohesive force
adhesive force
frictional force
<div>gravitational force</div>
|
| 26 |
The direction of angular velocity is along |
Tangent to the circle
Axis of rotation
Inward the radius
Out ward of the radius
|
| 27 |
If a car moves with a uniform speed of 2 ms-1 in a circle of radius 0.4m. Its angular speed is |
<div>4 rad. s<sup>-1</sup></div>
<div>1.6 rad. s<sup>-1</sup></div>
5 rad. s<sup>-1</sup>
<div>2.8 ms<sup>-1</sup></div>
|
| 28 |
In case of planets the necessary acceleration is provided by |
Gravitational force
coulomb force
frictional force
centripetal force
|
| 29 |
Ten second after an electric fan is turned on, the fan rotates at 300rev/min. its average angular acceleration is |
30 rad/s<sup>2</sup>
3.14 rad/s<sup>2</sup>
30 rev/s<sup>2</sup>
<div>500 rev/s<sup>2</sup></div>
|
| 30 |
The angular analogue of linear displacement is called |
angular velocity
angular displacement
angular momentum
moment of force
|
| 31 |
When a particle moves in a circle the angle between it linear velocity and the angular velocity is always |
0°
180°
90°
none of them
|
| 32 |
The time period of revolution of geostationary satellite is |
1440 minutes
24 minutes
84 minutes
none of these
|
| 33 |
A car of 1000kg traveling at 20m/sec rounds a curve of radius 100m. Find the necessary centripetal force |
4 x 10<sup>3</sup>
kg m/s<sup>2
</sup>
<div>3 x 10<sup>3</sup> kg m/s<sup>2</sup></div>
<div>5 x 10<sup>3</sup>kg m/s<sup>2</sup></div>
<div>4.5 x 10<sup>3</sup>kg m/s<sup>2</sup></div>
|
| 34 |
A ball is thrown vertically upwards. Neglecting air resistance, which statement is correct? |
The kinetic energy of the ball is greatest at the greatest height attained
The potential energy of the ball increase uniformly with time during the ascent
By the principle of conservation of momentum. The momentum of the ball is constant throughout its motion
By the principle of conservation of energy, the total energy of the ball is constant throughout its motion
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| 35 |
A man weighing 500 N carries a load of 10 kg to the top of a building in 4 minutes. The work done by the man is 6 × 𝟏𝟎4 J. If he carries the same load in 8 minutes, the work done by the man will be: |
3 × 10<sup>4</sup> J
6 × 10<sup>4</sup>J
9 × 10<sup>4</sup>J
<div>12× 10<sup>4</sup> J</div>
|
| 36 |
A person holds a bucket of weight 60N. He walks 7 m along the horizontal path and then climbs up a vertical distance of 5 m. The work done by the man is: |
300 N-m
420 N-m
720 N-m
none of these
|
| 37 |
A man M1 of mass 80 kg runs up a staircase in 15s. Another man M2 also of mass 80 kg runs up the same staircase in 20s. The ratio of the power developed by them will be |
1
4/3
16/9
none of these
|
| 38 |
An engine pumps up 100 kg of water through a height of 10m in 5s. Given that the efficiency of the engine is 60%, what is the power of the engine? (Take g = 10ms-2) |
33 kW
3.3kW
0.33kW
0.033kW
|
| 39 |
An engine pumps out 40 kg of water in one second. The water comes out vertically upwards with a velocity of 3ms-1 . What is the power of engine in kilowatt? |
1.2kW
120kW
12kW
1200kW
|
| 40 |
An elevator's motor produces 3000 W power. The speed With Which it can lift a 1000 kg load is: |
30.6ms<sup>-1</sup>
0.306ms<sup>-1</sup>
3.06ms<sup>-1</sup>
300.3ms<sup>-1</sup>
|