Galaxies emit
radio waves and X-rays
ultraviolet light waves
visible light waves
All the above
Correct Answer :
D. All the above
Related Questions
The function of a ruse wire is
to stabilise the voltage
to decrease the current supply
to increase the current supply
to prevent an unduly high current from passing through a circuit
Out of the following which is an insulator?
Silver
Copper
Nichrome
Dry wood
The study of astronomy include a
astrology
astrophysics
astrometry
Both (b) and (c) above
A pressure gauge for fluids is called
a hydrometer
a manometer
a lactometer
an anemometer
The completely dark portion of a shadow of an object is known as
umbra
penumbra
image
black portion of light
Pieces of camphor placed on water move about rapidly. This is because of
diffusion
viscosity
surface tension
capillarity
Which metal is used in storage batteries?
Copper
Lead
Tin
Iron
In the fuse of an electrical installation blows out
replace the fuse by a thin wire
replace the fuse by a thick copper wire
replace the fuse by a fuse wire of proper rating
replace the fuse by nichrome wire
Fish and other aquatic creatures can live inside a deep frozen pond because
fish are cold-blooded animals
ice is a bad conductor of heat
there will always be water just beneath the ice level
they can adapt themselves to live in ice
The planet with the reddish tinge is
Jupiter
Mars
Mercury
Saturn
The attraction of unlike molecules at the common surface is known as
adhesion
cohesion
surface tension
capillarity
X-rays are used
in hospital in the treatment of malignant growth
to reveal hidden flaws in metal castings and welded joints
to detect alterations made in works of art
All the above
Isotones are species of atoms containing
same number of protons but different number of neutrons
same number of neutrons but different number of protons
the same total number of protons and neutrons
same number of protons and different number of electrons
The solar wind is composed of
outward stream of protons and electrons on the surface of the sun during solar flares and sun-spot activity
plasma
ionized gas
All of these
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 workman was working on a rail track. A young boy at a distance holds his ear close to the railway track. The boy was able to hear the sound of each blow or the workman twice. It is because
speed of sound is greater in steel than in air
speed of sound is greater in air than in steel
part of sound waves is reflected between rail tracks
the boy's ears are at a different distance from the source
A piece of cork la embedded inside an ice block which floats in water. What will happen to the level of water when all ice melts?
It will go down
It will come up
It will remain at the same level
First it will go down and it will come up
A stationary elevated object has
kinetic energy
potential energy
momentum
both potential and kinetic energy
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
is more than at sea level
is equal to that sea level
is less than at sea level
depends on the surrounding temperature
The method used to separate aluminium from a alumina is
electroplating
electrotyping
electrolysis
distillation
The principle of equivalence of mass and energy was established by
Dalton
Rutherford
Einstein
Planck
Who first established the fact that the earth revolves round the sun?
Sir Isaac Newton
Kepler
Copernicus
Ptolemy
Pyrometers are instruments used
for measuring the velocity of wind
in the manufacture of fireworks
in finding the coefficient of apparent expansion of a liquid
for measuring high temperatures
An ammeter has
a high resistance
a very low resistance
no resistance at all
resistance of 400 � w
The shadow below a tree has bright spots in it because
light comes through circular gaps between the leaves
the leaves are circular
the rays bend to form circular spots
the gaps between the leaves act as pin holes
In a vacuum the following three articles are dropped at the same time and from the lame height. Which will reach the ground quicker?
a stone
a piece of wood
a feather
all will reach the ground at the same time
Skating on ice is possible because
the surface of ice is smooth
ice is cold
the pressure on the ice due to skate melts the ice by lowering its melting point forming a thin film of water
the pressure on the ice due to skate raises its melting point
A tube light works on the principle of
chemical, heating and magnetic effects of electricity
discharge of electricity through gases
the action of ultraviolet radiation on certain fluorescent materials
Both (b) and (c) above
Heat is transmitted from one end of a metal rod to its other end by the method of
conduction
convection
radiation
sublimation
To concentrate light on the defective teeth, the dentists use
convex mirrors
concave mirrors
convex lens
concave lens