Phy Ls 6 Light

Question 1

A concave mirror can form

Answer 1

Both real and virtual image

Question 2

Focal length is represented by

Focus is represented by

Answer 2

f

F

Question 3

What are spherical mirrors

Answer 3

Concave mirror and convex mirror together are called as spherical mirrors or curved mirrors

Question 4

Define focal length and write its formula and unit

Answer 4

The focal length is the distance between the the pole(P) of of a mirror and the focus of the mirror(F)
It is represented by f (small f)
Focal length (f) = radius of the spherical mirror
———————————————– (r/2)
2

Question 5

According to cartesion sign convention which mirror and which lens has negative focal length

Answer 5

Concave

Question 6

The mirror which can give An erect and enlarged image and same size inverted image

Answer 6

Concave

Question 7

Speed of light in vacuum

Answer 7

3 into 10 to the power metre per second

Question 8

Who was measure the speed of light

Answer 8

Armand Fizeau

Question 9

If an object is placed at the focus of a concave mirror where is the image formed

Answer 9

Infinity

Question 10

The velocity of light depends on

Answer 10

The nature of the medium in which it travels

Question 11

What is the sign for real and virtual image

Answer 11

For real image it is negative and for virtual image is positive

Question 12

Define optics

Answer 12

The branch of physics that deals with the properties and applications of light

Question 13

Define light

Answer 13

Light is a form of energy which travels as

Electromagnetic waves.

Question 14

Laws of reflection

Answer 14

The incident ray the reflected ray and the normal at the point of incidence or lie on the same plane

The angle of incidence is equal to the angle of reflection

Question 15

Examples for optical instruments

Answer 15

Microscopes in laboratories
Cameras
Projectors
Telescope
Binoculars

Question 16

All distances are measured from the_____of the mirror

Answer 16

Pole

Question 17

In which side of the mirror is the object always plays

Answer 17

Left

Question 18

When was the speed of light first measured

Answer 18

In the year 1849

Question 19

What is the speed of light in vacuum express in terms of kilometres

Answer 19

300 ,000 km per second

Question 20

What is bioluminescence

And y organisms use that?

Answer 20

The ability of some organisms to make their own light.

They glow ir flash their light to scare off predators in the dark sea habitat