Q.41)-Electron microscope is more magnifier than light magnifying because
- Velocity of electron is less than velocity of light
- Wavelength of electron is less than the wavelength of light
- Electron contains more energy than particles
- More powerful lenses are used in electron microscope
Q.42)-A periscope works on the principle of
- Refraction
- Total internal reflection
- Diffraction
- Reflection
Q.43)-In mirrors the back surface is painted with a thin layer of
- Mercury
- Silver
- Red oxide
- Silver nitrate
Q.44)-Which of the following is used to split white light into different colours?
- Glass slab
- Convex lens
- Concave lens
- Prism
Q.45)-Spectacles used for viewing 3D films have
- Bifocal lens
- Convex lens
- Concave lens
- Polaroids
Q.46)-A concave lens always form an image which is
- Real and erect
- Virtual and erect
- Real and inverted
- Virtual and inverted
Q.47)-One can distinguish a telescope from a microscope by observing
- Length
- Colour
- Size of the lens
- Length and size of the lens
Q.48)-To get the magnified and virtual image mirror is used
- Plane mirror
- Convex mirror
- Concave mirror
- Concave lens
Q.49)-Which of the following always makes the smaller image of body, which is played in front of it?
- Plane mirror
- Convex mirror
- Convex lens
- Concave mirror
Q.50)-The image formed by specific mirror; legs appears as of same size but head and his body appears smaller than its real size, when person stands in front of mirror. What is the nature of mirror?
- Plane and concave
- Convex and concave
- Convex and plane
- Plane