MOTION
Acceleration is a vector quantity, which indicates that its value
(a) Is always negative
(b) Is always positive
(c) Is zero
(d) Can be positive, negative or zero
(d) Can be positive, negative or zero
In a rocket, a large volume of gases produced by the combustion of fuel is allowed to escape through its tail nozzle in the downward direction with the tremendous speed and makes the rocket to move upward.
Which principle is followed in this take off of the rocket?
(a) Moment of inertia
(b) Conservation of momentum
(c) Newton’s third law of motion
(d) Newton’s law of gravitation
Conservation of momentum
A man is carrying the heavy luggage from one platform to the other of a Railway station but still according to the logics of science his work done is said to be zero. Can you opt out the correct reason?
(a) The force is acting along the direction of displacement of luggage
(b) The force is acting perpendicular to the direction of displacement of luggage
(c) The force is acting opposite to the direction of displacement of luggage
(d) None of these
(b) The force is acting perpendicular to the direction of displacement of luggage
The sound can travel in air when:
(a) Particles of medium travel from one place to another
(b) There is no moisture in the atmosphere
(c) Disturbance travel from one place to another
(d) Both particles as well as disturbance travel from one place to another
c) Disturbance travel from one place to another
The mass of moon is about 0.012 times that of the earth and its diameter is about 0.25 times that of earth. The value of G on the moon will be:
(a) Same as that on the earth
(b) About one-fifth of that on the earth
(c) About one-sixth of that on the earth
(d) About one-fourth of that on the earth
(a) Same as that on the earth
The acceleration of a body from a velocity –time graph is
(a) Is denoted by a line parallel to the time axis at any point on the distance axis
(b) Equal to the slope of the graph
(c) Area under the graph
(d) Is denoted by a line parallel to the distance axis at any point on the time axis
(b) Equal to the slope of the graph
A water tank filled upto 2/3 of its height is moving with a uniform speed. On sudden application of the brake, the water in the tank would
(a) Move backward
(b) Move forward
(c) Come to the rest
(e) Be unaffected
Move forward
When a body falls freely towards the earth, then its total energy
(a) Decreases
(b) Increases
(c) First increases and then decreases
(d) Remains constant
(d) Remains constant
We can distinguish between a man’s voice and a woman’s voice of the same loudness even without seeing them. This is due to a characteristic of sound which measures the shrillness of sounds. Can you choose the correct unit of the quantity on which this characteristic of sound depends?
(a) hertz
(b) meter/second
(c) meter
(d) unitless
(a) hertz
An apple falls from a tree because of the gravitational attraction between the earth and the apple. If F1 is the magnitude of the force exerted by the earth on the apple and F2 is the magnitude of the force exerted by the apple on the earth, then
(a) F1 is very much greater than F2
(b) F2 is very much greater than F1
(c) F1 and F2 are equal
(d) F1 is only a little greater than F2
(c) F1 and F2 are equal
Distance covered by the body during the interval from 10sec to 20 sec is
(a) 180
(b) 200
(c) 240
(d) 270
(d) 270
The seat belts are provided in the cars so that if the car stops suddenly due to an emergency braking, the persons sitting on the front seats are not thrown forward violently and saved from getting injured. Can you guess the law due to which a person falls in forward direction on the sudden stopping of the car?
(a) Newton’s first law of motion
(b) Newton’s second law of motion
(c) Newton’s third law of motion
(d) Newton’s law of gravitation
Newton’s first law of motion
When a body like earth is moving in a circular path the work done in that case is zero because:
(a) Centripetal force acts in the direction of motion of the body
(b) Centripetal force acts along the radius of circular path
(c) Gravitational force acts along the radius of circular path
(d) Centrifugal force acts perpendicular to the radius of circular path
(b) Centripetal force acts along the radius of circular path
A key of mechanical piano is first struck gently and then struck again but much harder this time. What kind of change in sound will you observe in the second case:
(a) Sound will be louder but the pitch will not be different
(b) Sound will be louder and the pitch will also be higher
(c) Sound will be louder but the pitch will be lower
(d) Both loudness and pitch will remain unaffected
(c) Sound will be louder but the pitch will be lower
The earth and the moon are attracted to each other by gravitational force. The earth attracts the moon with a force that is:
(a) More than that exerted by the moon
(b) Same as that exerted by the moon
(c) Less than that exerted by the moon
(d) Not related to that exerted by the moon
(b) Same as that exerted by the moon
What does the slope of distance - time graph give?
(a) Acceleration
(b) Uniform speed
(c) Speed
(d) both[b] and [c] depending upon the time of graph
Speed
When a balloon held between the hands is pressed, its shape changes. This happens because:
(a) Balanced forces act on the balloon
(b) Unbalanced forces act on the balloon
(c) Frictional forces act on the balloon
(d) Gravitational force acts on the balloon
Balanced forces act on the balloon
A car is accelerated on a leveled road and attains a velocity 4 times of its initial velocity. In this process, the kinetic energy of the car
(a) Becomes twice to that of the initial
(b) Becomes four times to that of the initial
(c) Remains the same
(d) Becomes 16 times to that of the initial
(d) Becomes 16 times to that of the initial
Before the main shock waves, the earthquake produces the characteristic sound waves which some animals like rhinoceros can hear. Can you guess the kind of sound waves produced here?
(a) Infrasonic sounds
(b) Ultrasonic sounds
(c) Audible Sounds
(d) None of these
) Infrasonic sounds
A stone is released from the top of a tower of height 19.6 m. Then its final velocity just before touching the ground will be:
(a) 384.16 m/ s
(b) 196 m/s
(c) 19.6 m/s
(d) 3841.4 m/s
(Take g = 9.8 m/s2)
(c) 19.6 m/s
A player moves along the boundary of a square ground of side 50 m in 200 sec.The magnitude of displacement of the farmer at the end of 11 minutes 40 seconds from his initial position is
(a) 50 m
(b) 150 m
(c) 200 m
(d) 50√2 m
(d) 50√2 m
The speed of a car weighing 1500 kg increases from 36 km/h to 72 km/h uniformly. What will be the change in momentum of the car?
(a) 15000 kg km/h
(b) 15000 kg m/s
(c) 54000 kg m/s
(d) 54000 g m/s
15000 kg m/s
The momentum of a bullet of mass 20 g fired from a gun is 10 kg m/s. The kinetic energy of this bullet in kJ will be:
(a) 25
(b) 2.5
(c) 0.25
(d) 5
(b) 2.5
On increasing the temperature, the speed of sound in air:
(a) Increases
(b) Decreases
(c) Does not change
(d) First increases then becomes constant
(a) Increases
Two particles are placed at some distance. If the mass of each of the two particles is doubled, keeping the distance between them unchanged, the value of gravitational force between them will be:
(a) 1/4 times
(b) 4 times
(c) 1/2 times
(d) Unchanged
(b) 4 times