For accurate scientific work, temperatures are often measured by
mercury thermometers
alcohol thermometers
platinum resistance thermometers
thermoelectric thermometers
Correct Answer :
C. platinum resistance thermometers
Related Questions
We see the flash of lightning before hearing the thunder because
light travels very much faster than sound
sound travels faster than light
lightning occurs nearer than thunder
both travel at the same speed
When the earth reaches its perihelion
it is nearest to the moon
it is nearest to the sun
it is nearest to Pluto
it is farthest from the sun
Lightning conductors are made of
iron
chromium
copper
steel
In compact porous soil, the rising of the water is due to
capillarity
cohesion
adhesion
viscosity
A timer in a race is at the finish line. He should start his stop watch
as soon as he hears the report of the gun
the moment he sees the flash
either (a) or (b) since that makes no difference
None of the above
If a man wants to hear clearly the echo of a sound produced by him from a hill, the hill should be away from him by a minimum distance of
330 m
33 m
16.5 m
165 m
The escape velocity of a satellite projected from the surface of the earth is independent of
the mass of earth
the mass of the satellite
the radius of the earth
gravitation of the earth
The velocity of sound in air increases with
the rise of temperature
rise of its frequency
decrease in humidity
fall of temperature
A hydrogen bomb is based on
nuclear fusion
nuclear fission
Both (a) and (b) above
Neither (a) nor (b)
To produce beats it is necessary to have two waves
travelling in opposite direction
of slightly different frequencies
of equal wavelength
of equal amplitude
Which is the densest planet of the solar system?
Sun
Jupiter
Mercury
Earth
In hot climatic conditions, the buildings are painted white because
white paint is economical
it does not fade off
it does not crack with higher temperature
white coating is a bad conductor of heat and reflects heat rays that fall on it, thus keeping the inside cool
A radio set that uses valves does not start operating immediately when it is switched on whereas a set containing only tranaistors operates immediately. The reason for this is that
the valve filaments have low resistance
valve-radio sets work at a higher voltage
transistor set has a low resistance
filaments of the valves cake time to beat up and function
When a satellite is In a geostationary orbit the force keeping it in orbit Is
zero
the centrifugal force
reaction due to steady burning of fuel
the gravitational pull on the body by the earth is the weight of the body which provides the centripetal force
X-rays are
deflected by electric field
deflected by magnetic field
slightly deflected by electric field and magnetic field
not deflected by electric and magnetic fields
Mercury does not stick to glass because
cohesive forces between the mercury molecules are greater than adhesive forces between mercury and glass molecules
the adhesive forces between mercury and glass molecules are greater than the cohesive forces
both the cohesive and adhesive forces are equal
None of the above
Hot water is poured simultaneously in four metallic tumblers painted outside with different paints. After some time the water will be found to have cooled most in the tumbler painted.
rough white
rough black
shining white
shining black
It is difficult to bon potatoes at the top or a mountain because
the water available is hard
it is colder than at sea level
the potatoes become hard
the boiling point of water is lower at that height on account of low atmospheric pressure
A heavenly body similar in nature to the sun intensely hot glowing mass that produces its energy by thermonuclear reactions is
a planet
a meteor
a star
a comet
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
At temperature near OK, (zero kelvin) metals such as lead and tin become
insulators
semiconductors
superconductors
condenser
A hydraulic brake in an automobile uses
a fluid to transmit the braking force
the force applied by the driver
hydrogen gas and not any liquid
a vacuum brake
An electric kettle used for boiling hard water has a white scale deposited on its heating element. This consists or
sugar
sodium carbonate
common salt
carbonates of calcium and magnesium
Meteors
look like falling stars
are really pieces of rock or metal
burn up as they shoot through the air
All the above
Choose the correct answer
Microphone converts sound energy into electrical energy.
Electric fan converts electrical energy into mechanical energy.
Battery converts chemical energy into electrical energy.
All the above
Light from the sun reaches the earth in
2 minutes
4 minutes
12 minutes
8 minutes
Antiparticle of electron is
proton
antiproton
positron
neutron
The colour of a star is an indication of its
distance from the earth
age
temperature
size
Gamma radiations are used for
sterilising food stuff
controlling pests
cancer therapy
All of these
When water is cooled from 4�C to 2�C its density
increases
decreases
remains the same
first increases then decreases