The stars that shine brightly then dimly and then brightly are known as
meteors
binaries
variable stars
bright stars
Correct Answer :
C. variable stars
Related Questions
We always see only one side of the moon because
the sun comes in between the earth and moon
the moon is stationary
the time taken by the moon to rotate on its axis is the same as the time taken by it to revolve round the earth
moon revolves round the sun
The largest reserve of radioactive element which can be used in a nuclear reactor has been found in India, The name of the element is
Thorium
Uranium
Plutonium
Radium
The motion .of the pendulum of a wall clock is an example of
linear motion
vibratory motion
rotational motion
None of the above
The device used to record the sound is
a microphone
a headphone
a phonograph
an amplifier
If a body is taken from the earth to the moon
both its mass and weight will be different
its mass will be different but the weight will remain the same
its mass and weight will both remain unchanged
its mass will remain the same but weight will be different
Photo-electric cells convert
electrical energy into light energy
light energy into electrical energy
light energy into heat energy
electrical energy into heat energy
When the disturbed electrons of an exited atom transfer back into lower energy levels they emit energy in the form of electromagnetic wave pulses called
neutrons
electrons
phonons
photons
In a refrigerator, the refrigerant is
Nitrogen
Oxygen
Chlorine
Freon
Of the following types of electromagnetic radiation which has the longest wavelength?
ultraviolet rays
gamma rays
radio waves
infrared waves
In a dynamo
mechanical energy is converted to light energy
mechanical energy is converted to heat energy
mechanical energy is converted to electrical energy
electrical energy is converted to mechanical energy
A person does not sink in the Dead Sea because
the sea contains a large amount of other salts besides sodium chloride
the density of the person is less than the density of the Dead Sea water
of the surface tension due to salt water in the Dead Sea
of difference in mass
The ballistic missile, Agni 11, tested by India has a maximum range of
1000 km
1500 km
2000 km
500 km
When a ship floats on water, the weight or water displaced is
an indeterminate quantity
equal to the weight of the ship
greater than the weight of the ship
less than the weight of the ship
The hydraulic jack to lift heavy vehicles in automobile service stations is one of the applications of
Pascal's law
Principle of Archimedes
Boyle's law
Hooke's law
The principle of equivalence of mass and energy was established by
Dalton
Rutherford
Einstein
Planck
When two similar sources vibrate with slightly different frequencies, a regular rise and fall occurs in the loudness of tone. This phenomenon Is known as
doppler effect
beats
resonance
echo
If a body is taken from the earth to the moon
both its mass and weight will be different
its mass will be different but the weight will remain the same
its mass and weight will both remain unchanged
its mass will remain the same but weight will be different
When light passes from air to glass, its velocity in glass
increases
decreases
remains unchanged
first decreases then increases
In an electrical circuit, a fuse is connected
in the live wire
in the neutral wire
in the earth wire
anywhere
When a bowler spins a ball, it changes its direction in the air. This is due to
turbulence caused by the wind
buoyancy of air
unequal pressures acting on it
sudden change in the direction of the wind
When a body is partly or wholly immersed in a liquid the apparent loss of weight is equal to the weight of the liquid displaced by the submerged portion. This is known as
Pascal's law
Bernoulli's law
Archimedes' law
Boyle's law
The SI unit of electric current is
the ampere
the volt
the ohm
the coulomb
In experiments on static electricity the standard method for obtaining small amounts of positive electricity is to rub
a glass rod with flannel
an abonite rod with flannel
a glass rod with silk
Any of the above
The aneroid barometer uses
mercury
distilled water
alcohol
does not use any liquid
The unit of power in SI is
Joule
Newton
Joule/Sec
Erg/Sec
How is it that Pluto is not always the farthest planet of the solar system?
Each planet becomes the farthest planet in its turn. Now it is the turn of Piuto
The Sun is now in the zodiac in which it is nearest to outer planets
The eccentricity of Piuto's orbit being substantial, this orbit cuts the orbit of Neptune
Piuto belongs to other solar system
Sun spots are
the mountains found on the surface of the Sun
the dark patches on the sun having less temperature than the normal sun's surface
ionized gas found near the solar surface
the magnetic storms on the surface of the Sun
A ship sailing from a river to the sea
sinks less in the sea
sinks more in the sea
neither sinks more nor less in the sea
sinking more or less depends on sea
The planet that moves fastest around the sun is
Mars
Venus
Earth
Mercury
We cannot see and without the aid of a telescope
Neptune and Pluto
Jupiter and Saturn
Venus and Mars
Venus and Saturn