Mechanics: MCQ Test (50 questions)

Question 1 of 50

Two stones of different masses are dropped simultaneously from the top of a building.

Athe smaller stone reaches the ground first
BThe bigger stone reaches the ground first.
CBoth stones reach the ground at the same time.
DDepends on the composition of the stone

Question 2 of 50

Capillarity is not the sole reason for which one of the following?

Aink adsorption
Bgroundwater upwelling
CSpreading of a water drop on a cotton cloth
Dthe movement of water from a plant's roots to its foliage

Question 3 of 50

When milk is churned vigorously, why does the cream separate from it?

AWhen milk is churned vigorously, why does the cream separate from it?
BThe centrifugal force is less than the weight of the water.
CThe weight of water at the highest position of the bucket is reduced by
DThe cohesive force between the water and the bucket is greater

Question 4 of 50

What is the amount of matter in a steel sphere?

AWeight
BMass
Cdensity
Dvolume

Question 5 of 50

If an iron ball is dropped in a bucket filled with mercury, then-

AIt will settle to the bottom of the bucket.
BIt will float on the surface of the mercury.
Cit will dissolve
Dnone of the above

Question 6 of 50

Surface tension when soap is dissolved in water

Ahappens to
BIt increases.
Cremains unchanged
DFirst it decreases and then it increases.

Question 7 of 50

When the pendulum is taken to the moon, its time period is-

Awill remain the same
Bwill decrease
Cwill become zero
Dwill increase

Question 8 of 50

Food is cooked in less time in a pressure cooker because-

AThe temperature of boiling water decreases due to high pressure.
BIt is closed from all sides and hence is not affected by wind.
CThe temperature of boiling water increases due to higher pressure.
DThere is very little evaporation of the water used.

Question 9 of 50

What is the name of the force by which the Earth pulls all objects towards itself?

Apush
Bresistance
Cair pressure
Dgravity

Question 10 of 50

Ice floats in water but sinks in alcohol because-

AWater is more transparent than alcohol
BIce is formed by the freezing of water
CIce is a solid while alcohol is a liquid
DIce is lighter than water and heavier than alcohol

Question 11 of 50

Which of the following does not have a unit of Newton meter?

AForce
Bkinetic energy
CWork
Denergy

Question 12 of 50

What is the unit of power of a lens in SI system?

AWatt
BDiopter
COpter
Dmeter

Question 13 of 50

The work done to hold a 20 kg weight at a height of 1 m above the ground is

A20 joules
B200 joules
C981 joules
DZero Joules

Question 14 of 50

The SI unit of temperature among the following is—

ARéaumur scale
BKelvin
CAmpere
DCandla

Question 15 of 50

Consider the following statements regarding the light year: 1. A light year is a unit for measuring very long distances. 2. A light year is a unit for measuring very long time intervals. 3. A light year is a unit for measuring the intensity of light. Which of the given statements is/are correct?

A1, 2 and
B2 and 3 only
C1 and 2 only
Donly 1

Question 16 of 50

The wall below the dam is made thick because-

AThe pressure of the liquid increases with increasing depth
Bfluid pressure decreases with increasing depth
CThe density of the liquid increases with increasing depth.
DThe density of a liquid decreases with increasing depth

Question 17 of 50

The apparent weight of a person in a lift is less than the actual weight when the lift is going

Aup with acceleration
Bdown with acceleration
Cup with the same speed
Ddown at the same speed

Question 18 of 50

The unit of measurement of intensity of sound is-

Acandela
BAmpere
Cnautical miles
DDecibels

Question 19 of 50

A ball is dropped from a tall building with a uniform acceleration of 9.8 m/s2. What will its velocity be after 3 seconds?

A9.8m/s.
B9.6m/s
C294m/s
D39.3m/s

Question 20 of 50

Newton meter is the unit of-

Aof acceleration
Bof force
Cof power
Dof energy

Question 21 of 50

The unit of electrical quantity is-

AAmpere
BOm
CVolt
DCoulomb

Question 22 of 50

What causes the oil in the wick of a lamp to rise?

ACarboxylic groups in oil
Bcapillary phenomenon
Clow viscosity of oil
Dpressure difference

Question 23 of 50

Which of the following works on the basis of conservation of linear force?

ARocket
Bhelicopter
CJet
Dplane

Question 24 of 50

The unit of 'work' is-

AJoule
BNewton
CWatt
DDine

Question 25 of 50

Often, light thatched or tin roofs are blown away during a strong storm because-

ARoofs have complex shapes
BRoofs are not tightly fastened
CHigh velocity air flowing over the roof creates pressure on the roof surface and the pressure below the roof remains normal.
DThatched roofs blow away by strong winds

Question 26 of 50

To which country did the great scientist Archimedes belong?

ABritain
BGermany
CU.N.A.
DGreece

Question 27 of 50

When the Fortin barometer is taken to a high mountain, the mercury in the tube falls because-

AThe air here is relatively light.
BWith decrease in temperature the mercury level decreases
CThe atmospheric pressure there is low
Dthere the surface tension decreases

Question 28 of 50

body weight-

AIt is the same everywhere on the Earth's surface.
BIt is maximum at the poles.
Cis maximum at the equator
DIt is more prevalent on hills than on plains

Question 29 of 50

Why does a swimmer find it easier to swim in sea water than in river water?

AReduces pollution in sea water
BSea waves help a swimmer to float
CSea water has a higher density than ordinary water.
DThe ocean has a larger volume of water

Question 30 of 50

Why do clouds float in the atmosphere?

Alow pressure
Blow density
Clow viscosity
Dlow temperature

Question 31 of 50

Which of the following works on the basis of conservation of linear force?

A11.2km/s
B11.2m/s
C11.2 km/h
D10.2m/s

Question 32 of 50

What is the SI unit of 'force'?

AKelvin
BNewton
CPascal
DVolt

Question 33 of 50

Which of the following laws justifies the statement that matter can neither be created nor destroyed?

Alaw of conservation of energy
BLe Chatelier's law
CLaw of conservation of mass
Dlaw of osmosis

Question 34 of 50

Wide strips of wood or concrete are placed under the railway track, so that-

AIt can absorb shocks
BTo apply fish fillets correctly
Ckeep the tracks parallel
DThe pressure exerted by the train is reduced

Question 35 of 50

When detergent is added to pure water, the surface tension

Aincreases
Bhappens to
Cremains unchanged
Dbecomes infinite

Question 36 of 50

It is easier to roll a wooden cylindrical barrel than to drag it because-

AWhen it is pulled, the weight of the object acts
BThe force of friction in the rolling state is much less than the force of friction in the sliding state.
CThe barrel has a larger surface area in contact with the road when towing.
DAny option other than the above

Question 37 of 50

Why is it more difficult to breathe in the mountains than on the plains?

AAs altitude increases, air pressure decreases and oxygen requirement increases.
BMountain air is heavy and cannot be filled into the lungs.
CMountain air is impure, so we cannot breathe it.
Dnone of the above

Question 38 of 50

A boy suddenly sits down on a rotating round table. What effect will this have on the table's angular velocity?

Awill decrease
Bwill increase
Cwill remain the same
DNothing can be said

Question 39 of 50

The amount of buoyancy obtained by a solid partially or completely immersed in a liquid depends on—

Athe amount of liquid displaced by the solid
Bon the mass of the solid
Con the weight of the solid
Dnone of these

Question 40 of 50

When the speed of a moving object doubles, its kinetic energy-

Adoubles up
Bquadruples
Cremains the same
Dincreases threefold

Question 41 of 50

At which of the following places will the value of 'g' (gravity) be the highest?

AOn top of Mount Everest
Bon top of Qutub Minar
CAt the equator
DAt camp in Antarctica

Question 42 of 50

Before take-off, the airplane is run on the race track of-

Ato reduce the working air pressure
BTo increase the working air pressure
CTo reduce the frictional force between the aircraft and the ground
DTo increase the frictional force between the ground and the air by using air pressure

Question 43 of 50

Will remain unchanged when the quantity of the substance changes?

Avolume
BBurden
CMass
Ddensity

Question 44 of 50

Dynamo converts-

Ahigh voltage to low voltage
Belectrical energy into mechanical energy
Cmechanical energy into electrical energy
Dlow voltage to high voltage

Question 45 of 50

A corked bottle filled with water will break on freezing because-

AThe bottle shrinks when frozen
BThe volume of water decreases when it freezes
CThe volume of water increases when it freezes
Dglass is a bad conductor of heat

Question 46 of 50

Why does a cyclist lean while taking a turn?

AWhy does a cyclist lean while taking a turn?
BIt tilts so that the center of gravity remains within the base, preventing it from falling
CIt tilts to apply pressure to the wheels to travel along a curved path
DHe swerves to get around the curve faster

Question 47 of 50

When the mercury in the barometer suddenly falls, what does it indicate?

Ahot weather
Bchilly weather
Cpossibility of thunderstorms
Ddry season

Question 48 of 50

small drop of oil spreads on water because

AThe viscosity of the oil is high
Bwater has high viscosity
COil has high surface tension
Dwater has high surface tension

Question 49 of 50

Which one of the following is not correctly matched?

ADecibel – unit of sound intensity
BHorsepower – Unit of power
CNautical mile – Unit of distance in navigation
DCelsius - unit of heat

Question 50 of 50

What should a person do to reduce his (angular) speed on a freely rotating platform?

Ajoin your hands together
Braise your hands up
CSpread your hands outwards
DSit down with your hands raised