Sound waves In 'air travel faster if
frequency is higher
wavelength is smaller
pitch is smaller
air is warmer
Correct Answer :
D. air is warmer
Related Questions
Water kept in an earthen pot is less cool on rainy days than in summer because during the rainy days
the pores in the pot are closed
rain water stops oozing out from the pores
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surface of the pot becomes damp
To produce beats it is necessary to have two waves
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It is more difficult to walk on ice than on a concrete road because
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is given by the vertical height
cannot be measured with it
u) can be measured by both the methods described above
For viewing objects placed at a higher level from a position at a lower level, the instrument used' Is known aa
telescope
spectrometer
microscope
periscope
Cosmic rays are
powerful X-rays falling on the earth from space
ultraviolet rays from the sun
gamma rays from radioactive minerals
very energetic radiation falling upon the earth from outer space consisting chiefly of charged particles
Photo-electric cells convert
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light energy into heat energy
electrical energy into heat energy
Alternating Current (AC) is more advantageous than direct current because
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The ballistic missile, Agni 11, tested by India has a maximum range of
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1500 km
2000 km
500 km
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current may pass to the earth in case of a short circuit without doing any harm to the person
A projectile is fired at an angle with the horizontal with a small velocity. Its horizontal range will be maximum when the angle with the horizontal is
0°
30°
45°
60°
The radius of curvature of a spherical mirror is
equal to half its focal length
equal to its focal length
twice its focal length
not related to its focal length
The phenomenon of spontaneous disintegration of certain heavy nuclei is termed
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fission
fusion
implosion
Bats flying in the dark avoid obstacles because
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their eyes are sensitive to darkness
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Oersted
Faraday
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The unit of power in SI is
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4.3 years
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longitudinal
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it will fall down at the same place where the string breaks
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Columbus
Archimedes
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the greenhouse effect
the good conducting power of the metal body
the double layered wind shield
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a meteor
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a comet
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longitudinal
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Commonly used safety fuse wire is made of
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Lead
Nickel
An alloy of tin and lead