the forces of cohesion of the molecules within are very much less in them
the forces of cohesion are very large
the forces of adhesion are large
the forces of adhesion are less
mercury thermometers
alcohol thermometers
platinum resistance thermometers
thermoelectric thermometers
attract each other
repel each other
neither attract nor repel
attract or repel depending upon the conditions
transmutation
fission
fusion
radioactivity
alternating current of very high frequency
alternating current of very high voltage
a very large direct current
a high voltage direct current
mininuclear reactor
a dynamo
a thermopile
solar cells
16 hours
12 hours
20 hours
24 hours
planets do not have light of their own whereas stars shine by their own light
planets do not twinkle like stars
planets are much smaller than stars
All the above
ultraviolet rays
gamma rays
radio waves
infrared waves
1
infinite
0
4
umbra
penumbra
image
black portion of light
a planet
a meteor
a star
a comet
Tin
Lead
Nickel
An alloy of tin and lead
diffusion
effusion
vaporisation
sublimation
one
two
three
infinite
Crown glass
Water
Flint glass
Diamond
0° C
-15° C
4° C
15° C
so that they may reflect thermal radiation from outside and minimise such radiation from them
so that they may absorb all radiation from outside
to make them attractive to look at
because they take high polish
appears to increase
appears to decrease
does not change at all
first increases then decreases
HJ Bhabha
SS Bhatnagar
V Sarabhai
CV Raman
18 km/sec
11.2 km/ sec
21 km/ sec
35 km/ sec
to make it smooth and frictionless
to make it rust - proof
to reduce heat loss by radiation
to make it more durable
resistor
thermocouple
light bulb
neon tube
increasing the length of the coiled wire
increasing current supply
increasing the size of the iron core
All the above
for automatically maintaining a steady temperature
for measuring electricity
to reduce the voltage of electricity
for producing heat
the nature of the radiating surface
area of the radiating surface
temperature difference between the body and the surroundings
All the above
Dalton
Rutherford
Einstein
Planck
insulators
semiconductors
superconductors
condenser
can focus very rapidly as pictures change
is quicker than the brain
can see two images separated only if the interval' between seeing them is more than' one-tenth of a second
can shut out some of the light
enclosing it in a thick walled iron box
wrapping it with an insulator
by placing it inside a glass case
by surrounding it with fine copper gauze