Some persons are not able to see distant objects clearly because the image of the object is focused in front of the retina. This defect is known as
short sight
long sight
astigmatism
presbyopia
Correct Answer :
A. short sight
Related Questions
The SI unit of electric current is
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the volt
the ohm
the coulomb
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the ability of the ceiling, walls and floor to exclude unwanted sound
the use of furnishings made of sound absorbing materials
All the above
The electrical domestic tube light gives white fiourescent light because of
collision between molecules of filled gas under electric current
heavy current
vacuum inside the tube
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quinine sulphate solution
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deflected by magnetic field
slightly deflected by electric field and magnetic field
not deflected by electric and magnetic fields
The characteristics of a musical note are
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pitch
quality or timbre
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red
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green
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When sound waves travel from one medium to another, the quantity which remains unchanged is its
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frequency
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increases slightly
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breakup of the nucleus of a heavy atom into two nearly equal halves emitting two or three neutrons and releasing large amounts of nuclear energy in the process
the scattering of neutrons
formation of heavier nucleus
A lightning conductor installed in a building
does not allow the lightning to fall on the building at all
drives away the charged clouds
forces the lightning to fall on other buildings near that building
conducts the electric charges to the ground when lightning strikes the building
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Edison
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In an oil lamp, holes are provided below the chimney so that
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the convection current of air may be maintained to keep the lamp burning
the brightness of the lamp may be increased
All the above
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insulators
semiconductors
superconductors
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A hydrogen bomb is based on
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Both (a) and (b) above
Neither (a) nor (b)
A man Jumping out of a moving train is thrown
forward
backward
sideways
None of the above
Rain drops acquire spherical shape due to
viscosity
surface tension
friction
elasticity
Two tumblers stuck together can be separated by
pouring ice cold water into the inner tumbler
pouring ice cold water on the outer tumbler
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decreasing the radius of the capillary tube
increasing the radius of the capillary tube
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burst after reaching some height
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will decrease
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used by warships and military aircraft to locate enemy submarines
used by ships to determine the depth of water beneath them
a detective device that uses sound to locate under - water objects
All the above
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