Q.51)-What is a zoom lens?
  • A lens with a definite focal length
  • A lens with a transitional focal length
  • It is used in radio telescopes
  • None of these
Q.52)-Dioptre is the unit of
  • Power of lens
  • Focal length of lens
  • Intensity of lens
  • Intensity of sound
Q.53)-Radio telescope are better than optical telescopes because
  • They can detect faint galaxies which cannot be done by optical telescope
  • They can even work in cloudy conditions
  • They can work during day and night
  • All of the above
Q.54)-To eliminate the glare of headlight in motorcars
  • Polaroid's are used
  • Glass prism are used
  • Thin films are used
  • Filters are used.
Q.55)-The outer white part of the eye that protects the inner structure is
  • Iris
  • Sclera
  • Retina
  • Cornea
Q.56)-Person who is color blind can not distinguish between
  • Black and yellow
  • Red and green
  • Yellow and white
  • Green and blue
Q.57)-The least distance of distinct vision is
  • 35 cm
  • 25 cm
  • 45 cm
  • 15 cm
Q.58)-Distant objects are visible as little out of focus in the condition
  • Presbyopia
  • Hpermetropia
  • Astigmatism
  • Myopia
Q.59)-Sensitivity of human eye is maximum in the
  • Violet region
  • Green region
  • Blue region
  • Red region
Q.60)-A man can not see clearly beyond 10 meters. The disease he suffers from.
  • Far sight
  • Myopia
  • Cataract
  • Hypermetropia