Optics

Question 1

Laws of reflection

Answer 1

1. the angle of incidence is equal to the angle of reflection.
2. The incident ray, the reflected ray and the normal all lie on the same plane

Question 2

Laws of Refraction

Answer 2

1. Snell’s law - n= sin i / sin r, where n = refractive index (constant)
2. the incident ray, the normal and the refracted ray are on the same plane

Question 3

Refraction

Answer 3

The bending of a wave as it passes from one medium to another

Question 4

Lens formula

Answer 4

1/u +1/v = 1/f

Question 5

Power of a lens formula

Answer 5

P = 1/f (diopters) (1/m or m to the -1)

Question 6

Magnification Formula

Answer 6

image size / object size = v/u

Question 7

Critical angle (defintion)

Answer 7

the angle of incidence in the denser medium for which the angle of refraction will be 90 degrees

Question 8

Critical angle (Formula)

Answer 8

n = 1/ sin C

Question 9

Total Internal Reflection

Answer 9

When light is going from a denser medium to a rarer one.

This occurs when the angle of incidence in the denser medium is greater than the critical angle

Question 10

Light

Answer 10

Light is a form of Energy that travels away from it’s source at a speed of about 3 x 10 to the 8 m/s

Question 11

Reflection

Answer 11

the bouncing of light off an object

Question 12

Virtual Image

Answer 12

a virtual image is the apparent intersection of rays

Question 13

Real image

Answer 13

image formed by the actual intersection of light rays

Question 14

Parallax

Answer 14

the apparent movement of one object relative to the motion of the observer is called the parallax the object is farthest away appears to move with the observer

Question 15

Refractive index of a medium

Answer 15

ration of sine of the angle of incidence to the sine of the angle of refraction when light travels from a vacuum into that medium

Question 16

Long Sighted

Answer 16

can see distant objects, not near ones

corrected with a convex lens

Question 17

Short Sighted

Answer 17

can see near objects, not distant ones

corrected with concave lens

Question 18

Refractive index between two media

Answer 18

sin i / sin r

when light travels from one of those media into the other

Question 19

Optical Fibre

Answer 19

A very thin transparent rod through which light can travel by total internal reflection

Question 20

Concave mirror

Answer 20

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Question 21

Convex mirror

Answer 21

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Question 22

Converging Lens

Answer 22

()

Question 23

Diverging Lens

Answer 23

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