HORIZON INTERNATIONAL BILINGUAL SCHOOL name: 2. TERM, 1.
EXAMINATION PHYSICS 8th Grade Surname:
2) A person stands in front of a mirror, figure. How much of
the
mirror is used to see from eye to toes?
3) A ray of light strikes a plane mirror at an angle of
incidence of
60, is reflected from the mirror and then strikes a second
plane
mirror placed so that the angle between the mirrors is 45.
The
angle of reflection at the second mirror, in degrees, is
A 15 B 25 C 45 D 65 E 75
4) Figure below shows a ray of light PQ striking a mirror AB.
The
mirror AB and the mirror CD are at right angles to each
other.
QN is a normal to the mirror AB.
6) What happens when light travels from air into glass?
A. It speeds up. B. It travels at 300,000 km/s. C. It slows
down. D. It travels at the speed of sound.
7) As shown in the figure, a luminous object is placed
between
mirrors K and L. After its rays are reflected by mirror K and
then
by mirror L, what does the final image look like?
8) Light ray I incident upon the system of plane mirrors 1 and 2
returns back along the same path after being reflected by mirror 2.
What are the angles of reflection in mirrors 1 and 2?
9) In the diagram below which of the rays A to E is most likely
to
represent the ray emerging from the parallel- sided sheet of
glass?
10) A narrow beam of white light is shown passing through a
glass
prism and forming a spectrum on a screen,
a) What is the effect called? b) Which colour of light appears
at (i) A, (ii) B?
11)In 1987, a supernova was observed in a neighboring galaxy.
Scientists believed the galaxy was 1.66X1021 m away. How many years
prior to the observation did the supernova explosion actually
occur? a) 5.53x103 yr b) 5.53x1012 yr c) 1.75x105 yr d) 1.74x1020
yr 12) Which of the following light color combinations is
incorrect?
a) Red plus green produces yellow. b) Red plus yellow produces
magenta. c) Blue plus green produces cyan. d) Blue plus yellow
produces white.
1) In figure below the completely dark region on the screen
is
A) PQ B) PR C) QR D) QS E) RS
5) A light ray is incident on mirror 1 with an angle of 30,
as
shown in the figure on the right. What is the angle between
the incident ray and the ray reflected from mirror 2?
A) all B) half C) quarter D) double E) 1/3
13) Which diagram shows what happens when a ray of white
light passes through a prism?
14) The diagram shows the dispersion of white light by a
glass
prism.
15) Why does dispersion occur when white light enters the
glass?
A) The frequency of red light decreases more than that of violet
light. B) The frequency of violet light decreases more than that of
red light. C) The speed of red light decreases more than that of
violet light.
D) The speed of violet light decreases more than that of red
light.
16)A rough surface will scatter incoming light rays in different
directions, as shown by the yellow light rays in this diagram: The
reason for the scattering is because
a) the light rays strike the rough surface at different angles.
b) the light rays are absorbed when they strike a rough surface. c)
the rough surface refracts light rays. d) the light rays do not
obey the law of reflection on a rough surface.
19) Figure below shows a ray of light striking mirror 1 at point
X.
(a)On the figure, (i) draw the normal at X, (ii) draw the ray
reflected from mirror 1, (iii) mark the angle of incidence using
the letter i and the angle of
reflection using the letter r.
(b) Mirror 2 is parallel to mirror 1. The reflected ray from
mirror 1 strikes mirror 2. Compare the direction of the ray
reflected from mirror 2 with the incident ray at X. The reflected
ray from mirror 2 is
.....................................................................................
........................................................................................................
20) Figure below shows a ray of light, from the top of an object
PQ, passing through two glass prisms.
(a) Complete the path through the two prisms of the ray shown
leaving Q. (b) A person looking into the lower prism, at the
position shown by the eye symbol, sees an image of PQ.
Draw what he sees.
21) Figure below shows a ray of light incident on a mirror at
X.
The incident ray makes an angle of 50 with the surface of
the
mirror.
(i) Complete figure to show the normal and the reflected ray at
X. (ii) State the values of 1. the angle of incidence,
............................................... 2. the angle of
reflection. ...............................................
a) b)
c) d)
18) What color will you see when you mix the three main colors
as shown in the figure? F: G: H: K:
