Home
Current Affairs January 2024

What is the correct answer?

4

A rheostat is used

A. to increase the current flow in a circuit

B. to decrease the current flow

C. to measure the flow of electric current

D. Either (a) or (b) above

Correct Answer :

D. Either (a) or (b) above


Related Questions

What is the correct answer?

4

Sound travels fastest in

A. air

B. water

C. iron

D. vacuum

What is the correct answer?

4

Railway tracks are banked on curves so that

A. the necessary centrifugal force may be obtained from the horizontal component of the weight of the train

B. the frictional force between the track and the wheels is avoided

C. the necessary centripetal force may be derived from the horizontal component of the weight of the train

D. None of these

What is the correct answer?

4

The acoustical quality of a room depends on

A. the size and shape of the room

B. the ability of the ceiling, walls and floor to exclude unwanted sound

C. the use of furnishings made of sound absorbing materials

D. All the above

What is the correct answer?

4

Rays similar to X-rays but of smaller wave length that are given off by radioactive substances are

A. a -rays

B. � -rays

C. ? -rays

D. Cosmic rays

What is the correct answer?

4

In a refrigerator, the refrigerant is

A. Nitrogen

B. Oxygen

C. Chlorine

D. Freon

What is the correct answer?

4

An integrated circuit is more advantageous than a conventional circuit because

A. they make the electric equipment more reliable and easier for servicing

B. a faulty part of a conventional circuit may be difficult to locate and repair

C. if a part of the integrated circuit fails the entire circuit is simply replaced

D. All the above

What is the correct answer?

4

A spherical mirror is

A. a reflecting elliptical portion

B. a reflecting spherical surface

C. a parabolic reflecting surface

D. a flat reflecting surface

What is the correct answer?

4

Which metal is used in storage batteries?

A. Copper

B. Lead

C. Tin

D. Iron

What is the correct answer?

4

When a steel ball is placed on the surface of mercury, it does not sink because

A. of the surface tension of mercury

B. mercury is a semi-solid

C. of the high viscosity of mercury

D. the density of mercury is greater than that of steel

What is the correct answer?

4

Cosmic rays contain

A. protons and electrons

B. alpha particles

C. gamma rays

D. All the above

What is the correct answer?

4

A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will

A. increase

B. decrease

C. remain unaffected

D. have its shape changed

What is the correct answer?

4

When the resistance of a circuit increases the current will

A. increase

B. decrease

C. remain the same

D. None of the above

What is the correct answer?

4

A device used in a ship for the purpose of measuring the depth of the sea is

A. an altimeter

B. a fathometer

C. a hydrometer

D. a sonometer

What is the correct answer?

4

The motion .of the pendulum of a wall clock is an example of

A. linear motion

B. vibratory motion

C. rotational motion

D. None of the above

What is the correct answer?

4

The heat produced in a conductor due to the passage of a current through it is proportional to

A. the square of the current

B. the resistance of the conductor

C. the time for which the current flows

D. All the above

What is the correct answer?

4

The extremely luminous objects located at the centre of some distant galaxies and which are sources of high energy electromagnetic radiation are known as

A. Nebulae

B. Quasars

C. Meteors

D. Comets

What is the correct answer?

4

The spectrum of white light can be studied by

A. a microscope

B. a telescope

C. a stereoscope

D. a spectroscope

What is the correct answer?

4

The pressure of air at high altitude is less than the atmospheric pressure at the sea level. Hence the boning point of water at a hill top

A. is more than at sea level

B. is equal to that sea level

C. is less than at sea level

D. depends on the surrounding temperature

What is the correct answer?

4

The device used to record the sound is

A. a microphone

B. a headphone

C. a phonograph

D. an amplifier

What is the correct answer?

4

When an electric apparatus is fitted with a three core flexible lead the insulation on the three wires is distinctively coloured. The present international convention is

A. brown for earth, yellow for live, light blue for neutral

B. green for earth, yellow for live, brown for neutral

C. yellow for earth, green for live, brown for neutral

D. brown or red for live, light blue or black for neutral and green or yellow for earth

What is the correct answer?

4

Sound waves in air are

A. transverse

B. longitudinal

C. transverse and longitudinal

D. neither transverse nor longitudinal

What is the correct answer?

4

Photo-electric cells convert

A. electrical energy into light energy

B. light energy into electrical energy

C. light energy into heat energy

D. electrical energy into heat energy

What is the correct answer?

4

The source of electric energy in an artificial satellite is

A. mininuclear reactor

B. a dynamo

C. a thermopile

D. solar cells

What is the correct answer?

4

The distance between two bodies is halved. Now the force of attraction between them will be

A. half

B. one fourth

C. four times

D. two times

What is the correct answer?

4

A star contains

A. about 75% of hydrogen

B. 22% helium

C. traces of most other elements including oxygen, neon, carbon and nitrogen

D. All the above

What is the correct answer?

4

A body has fallen from a height. Just before touching the pound it has

A. lost all its potential energy and gained an equivalent amount of kinetic energy

B. gained potential energy and lost kinetic energy

C. gained kinetic energy as well as potential energy

D. lost kinetic energy as well as potential energy

What is the correct answer?

4

The maximum displacement of the particle in a mechanical wave motion is known as

A. amplitude

B. vibration

C. frequency

D. phase

What is the correct answer?

4

The brightest planet in the Solar System is

A. Jupiter

B. Mercury

C. Venus

D. Sirius

What is the correct answer?

4

The principle on which a Jet engine works is

A. conservation of mass

B. Newtonian law of action and reaction

C. conservation of angular momentum

D. None of the above

What is the correct answer?

4

A series of east moving still pictures can be made to appear as a moving picture because the eye

A. can focus very rapidly as pictures change

B. is quicker than the brain

C. can see two images separated only if the interval' between seeing them is more than' one-tenth of a second

D. can shut out some of the light