When a light ray is reflected repeatedly by a set of parallel plane mirrors, the intensity of light ray diminishes alter a few reflections. This is because of
poor reflection from the mirrors
scattering of light from the mirrors
absorption of some light by the mirrors
absorption of light by the atmosphere
Correct Answer :
C. absorption of some light by the mirrors
Related Questions
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
brown for earth, yellow for live, light blue for neutral
green for earth, yellow for live, brown for neutral
yellow for earth, green for live, brown for neutral
brown or red for live, light blue or black for neutral and green or yellow for earth
The sun continuously produces an enormous amount of energy. This is due to
nuclear fission
nuclear fusion
chemical combustion
boiling
When a bottle of perfume is opened in one corner of a room the smell spreads soon throughout the room. This is an example of
surface tension
capillarity
viscosity
diffusion
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
When are temperature resistance
increases
decreases
remains the same
first increases then decreases
The Space Application Centre for training in Satellite Communication Technology is located at
Bangalore
Mumbai
Ahmedabad
New Delhi
Increase in pressure
increases the melting point of ice
decreases the melting point of ice
has no effect on the melting point of ice
increases the volume of the ice
In a hydraulic pressure
force on each square centimetre of the small piston is less than the force on each square centimetre of the large piston
the distance the small piston moves is equal to the distance the large piston moves
applied pressure is equally transmitted throughout the liquid in all directions
force acting on small piston is equal to the force acting on large piston
Out of the following, name the fluorescent substance.
quinine sulphate solution
paraffin oil
fluorescein solutions
All the above
A body has fallen from a height. Just before touching the pound it has
lost all its potential energy and gained an equivalent amount of kinetic energy
gained potential energy and lost kinetic energy
gained kinetic energy as well as potential energy
lost kinetic energy as well as potential energy
A proton is
a quantum of light energy
a quantum of matter
a positively charged atomic particle
another name for positron
The speed of sound in a medium depends upon the properties of the medium such as
its density
its temperature
its elasticity
All the above
The aneroid barometer uses
mercury
distilled water
alcohol
does not use any liquid
Which metal is used in storage batteries?
Copper
Lead
Tin
Iron
A ruse wire is characterised by
high resistance and high melting point
high resistance and low melting point
low resistance and high melting point
low resistance and low melting point
The planet with the reddish tinge is
Jupiter
Mars
Mercury
Saturn
The period of a geostationary (synchronous) satellite orbiting the earth over the equator la
16 hours
12 hours
20 hours
24 hours
A simple mercury barometer is found in a slightly slanting position. The atmospheric pressure
is found by measuring the slanting height of the mercury column
is given by the vertical height
cannot be measured with it
u) can be measured by both the methods described above
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
An integrated circuit la more advantageous than a conventional circuit because
they make the electric equipment more reliable and easier for servicing
a faulty part of a conventional circuit may be difficult to locate and repair
if a part of the integrated circuit fails the entire circuit is simply replaced
All the above
When light travels from one medium to another there is a change in its
velocity
wavelength
frequency
Both (a) and (b) above
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
You want a supply of a small but constant current. Which of the following cells will you prefer?
Daniell cell
Leclanche cell
Dry cell
All the above
A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will
increase
decrease
remain unaffected
have its shape changed
The velocity of sound in a medium is
directly proportional to its pressure
inversely proportional to the square root of its pressure
directly proportional to the square root of its pressure
independent of its pressure
When an incident beam of light strikes the surface of a glass slab normally, the refracted beam
goes straight through without bending
gets deviated away from the normal
gets bent towards the normal
gets reflected
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 inability of a body to change its state of rest or uniform motion along a straight line is called its
momentum
velocity
acceleration
inertia
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 red colour of the setting sun is due to
the least scattered red colour reaching the eye
the dispersion of sun light occurred in air molecule in atmosphere
the diffraction of sunrays in atmospheric layers
interference of all the rays coming from the sun