### NEET Physics - New - Wave Optics

#### Question - 1

Consider sunlight incident on a slit of width ${ 10 }^{ 4 }$A. The image seen through the slit shall darkness as observed through the polaroid

• A Be a fine sharp slit white in colour at the centre
• B A bright slit white at the centre diffusing to zero intensities at the edges
• C A bright slit white at the centre diffusing to regions of different colours
• D only be a diffused slit white in colour

#### Question - 2

In a young's double slit experiment, the source is white light. One of the holes is covered by a red filter and another by a blue filter. In this case

• A There shall be alternate interference pattern of red and blue
• B There shall be alternate interference pattern of red distinct from that for  blue
• C There shall be no interference fringes
• D There shall be alternate interference pattern of red mixing with one for  blue

#### Question - 3

Consider the sunlight incident on a pinhole of width.${ 10 }^{ 3 }A$ The image of a pinhole seen on a screen shall be

• A A sharp white ring
• B Different from geometrical image
• C A diffused central spot, white in colour
• D diffused coloured region around a sharp central white spot

#### Question - 4

Consider the diffraction pattern for a small pinhole. As the size of the hole is increased

• A The size decrease
• B The intensity increase
• C The size increase
• D The intensity decrease

#### Question - 5

For light diverging from a point source

• A The wavefront is spherical
• B The intensity decrease in proportion to the distance squared
• C The wavefront is parabolic
• D The intensity at the wavefront does not depend on the distance

#### Question - 6

A source of light lies on the angle bisector of two plane mirror included at angle $\theta$The value of $\theta$so that the light reflected from one mirror does not reach the other mirror does not reach each other mirror will be

• A $\theta \ge 120°$
• B $\theta \ge 90°$
• C $\theta \ge 90°$
• D None of the above

#### Question - 7

The ratio of the speed of an object to the speed of its real image of magnification m in the case of a convex mirror is

• A $-\frac { 1 }{ { m }^{ 2 } }$
• B ${ m }^{ 2 }$
• C -xm
• D $\frac { 1 }{ { m } }$

#### Question - 8

In a concave mirror, an object is placed at a distance ${ d }_{ 1 }$ from the focus and the real image is formed at a distance ${ d }_{ 2 }$ from the focus. then the focal length of the nirror is:

• A $\sqrt { { d }_{ 1 }{ d }_{ 2 } }$
• B ${ d }_{ 1 }{ d }_{ 2 }$
• C ${ { (d }_{ 1 }{ /d }_{ 2 }) }^{ /2 }$
• D $\sqrt { { d }_{ 1 }{ /d }_{ 2 } }$

#### Question - 9

Which is not true for the image formed in a plane mirror? The image is

• A virtual
• B erect
• C laterally inverted
• D closer to the mirror than the object

#### Question - 10

The relation between focal length $f$ and radius of curvature $R$ of a spherical mirror is

• A $f=R$
• B $f=R/2$
• C $f=2 R$
• D none of these