P14 Light

Question 1

normal

Answer 1

line perpendicular to mirror

Question 2

angle of incidence, angle of reflection

Answer 2

angle between incident,reflected ray and the normal
law of reflection states they are equal

Question 3

forming an image with a plane mirror (and properties of that image)

Answer 3

virtual, upright and laterally inverted image

Question 4

real vs virtual images

Answer 4

A real image is formed where light rays actually converge after reflection or refraction, and it can be projected onto a screen.

A virtual image is formed when light rays appear to diverge from a point but don’t actually converge, and it cannot be projected onto a screen.

Question 5

specular vs diffuse reflection

Answer 5

Question 6

RP Refraction

Answer 6

compare angle of refraction with angle of incidence at the point the light ray enters the glass

Question 7

refraction rules

Answer 7

Question 8

red colour filter

Answer 8

transmits only red wavelengths, and absorbs all other wavelengths of the visible light spectrum

Question 9

colour combinations (4)

Answer 9

red + blue = magenta
red + green = yellow
blue + green = cyan
red + blue + green = white

Question 10

red coloured surfaces

Answer 10

reflect only red wavelengths, and absorbs all other wavelengths of the visible light spectrum

Question 11

transparent objects

Answer 11

Question 12

translucent objects

Answer 12

Question 13

why does refraction happen when moving from air to glass

Answer 13

different parts of the wavefront
enter the glass at different times
the velocity / speed (of light) is
less in glass
(so) one part of the wave front
changes speed before other
parts

Question 14

convex vs concave lense basics

Answer 14

convex = converging lense - brings ray together at a focus

concave = diverging lense - form virtual images

Question 15

ray diagram drawing rules

Answer 15

1: a ray parallel to the axis is refracted through the focus

2: a ray to the centre of the lens passes through undeflected

(3: a ray through the focus is refracted parallel to the axis)

Question 16

describing images

Answer 16

magnified/diminished
upright/inverted
real/virtual

(if image is inverted, it is almost definitely real)

Question 17

properties of images that concave lenses form

Answer 17

always:
upright
virtual (so drawn with dotted line)
diminished

Question 18

properties of images that convex lenses form (X)

Answer 18

outside 2F: diminished, inv, real
at 2F: same size, inv, real
F-2F: magnified, inv, real
at F: none
inside F: magnified, upright, virtual (to draw this you carry on the lines backwards as dotted lines until they converge as a virtual image)