Science 3rd prep

Lesson one
I) Complete the following statements :
1. The …………….. is the speed of moving object relative to the observer .
2. The total distance that a moving object covers divided by the total time taken
to cover this distance is known as ………………..
3. The uniform speed of a car is 90 km/hour,
4. When the average speed of an object equals the uniform speed
motion represents ………
5. The relative speed of moving object depends on ………
II) Write the scientific term :
1. The distance that a moving object covers within a unit time . […….…
2. The speed in which the object moves to cover equal distances at equal periods
of time .
3. The change in the position of a body by time relative to the position of another
body . [………….…..]
4. The simplest type of motion .
III) Put ( √ ) or ( × ) then correct what is wrong :
1. When a moving object covers equal distances at equal periods of time so it
moves with uniform acceleration
2. A car moves with regular speed covers 500 met
3. Average speed is the speed of a moving object relative to the observer ( )
4. Measuring the relative speed for a moving car d
speedometer which determines the speed value.
5. The relative speed of two moving bodies in the same direction equals the su
their speed .
Cairo Governorate
Nozha Directorate of Education
Nozha Language Schools
Ismailia Road
1
Unit one
Lesson one: Motion In One Direction
the speed of moving object relative to the observer .
The total distance that a moving object covers divided by the total time taken
to cover this distance is known as ………………..
niform speed of a car is 90 km/hour, its speed equals ………… m/s .
4. When the average speed of an object equals the uniform speed
motion represents ……………… motion .
5. The relative speed of moving object depends on ……………….
distance that a moving object covers within a unit time . […….…
The speed in which the object moves to cover equal distances at equal periods
The change in the position of a body by time relative to the position of another
body . [………….…..]
The simplest type of motion .
) then correct what is wrong :
moves with uniform acceleration
h regular speed covers 500 meters in 20 sec. its speed is 200 m/s
Average speed is the speed of a moving object relative to the observer ( )
Measuring the relative speed for a moving car depends on the presence of
which determines the speed value.
The relative speed of two moving bodies in the same direction equals the su
their speed .
Motion In One Direction
the speed of moving object relative to the observer .
The total distance that a moving object covers divided by the total time taken
speed equals ………… m/s .
4. When the average speed of an object equals the uniform speed , in this case the
…….…………..
distance that a moving object covers within a unit time . […….….……..]
The speed in which the object moves to cover equal distances at equal periods
[………..……..]
The change in the position of a body by time relative to the position of another
body . [………….…..]
[……………...]
( )
ers in 20 sec. its speed is 200 m/s
Average speed is the speed of a moving object relative to the observer ( )
the presence of
( )
The relative speed of two moving bodies in the same direction equals the sum of
( )
Department : Science
Form : 3rd
prep
Revision sheet

2
IV) Give reasons for :
1. The moving car seems stable to an observer moves with the same speed and
direction .
……………………………………………………………………………………
2. The uniform speed of a car can’t be obtained practically .
……………………………………………………………………………………
V) Define each of the following :
(1) Speed :…………………………………………………………………………….
(2) Irregular speed: …………………………………………………………………….
VI) Problem
1-A runner covered a distance of 100 meters to the north in 30 seconds , then 50
m to the east in 10 seconds , then 100 meters to the south in 15 seconds , then he
came back again to the starting point in 5 seconds . calculate .
a. The total distance covered by the runner .
……………………………………………………………………………..
b. The average speed of the runner .
…………………………………………………………………………….
2- A body covers a distance of 24 Km through 4 minutes then it covers 7.2 Km
through 3 minutes .
Calculate the average speed
………………………………………………………………………………………
....……………………………………………………………………………………

3
Lesson Two
Graphic Representation of moving in a straight line
I) Complete :
1. The value of change of an object’s speed in one second is ………………..
2. When an object moves with decelerating motion this means that its ………….
speed is greater than its ……………. Speed .
3. For a car moves with a regular speed , the ratio d / t is ………………
4. The ratio between the final speed and initial speed for an object moves with
accelerating motion is …………….. one .
1. The graph for a regular motion at uniform speed which is represented by a
straight line parallel to the ( ×) axis . [………..……….….]
2. The change of the object’s speed by equal values through equal period of time .
[…………………….]
3. The graph for a regular motion at uniform speed which is represented by a straight
line passes through – the origin point . […………………….]
III) What’s the difference between :
1. Speed – acceleration ( Definition – measuring unit )
……………………………………………………………………………………….
……………………………………………………………………………………….
2. The graphical relation ( distance – time ) and the graphical relation (speed – time)
for regular motion in a straight line at constant speed .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………

IV) What is meant by :
A body moves with acceleration equals zero
………………………………………………………………………………………..
V)-Problem :
1) A racing car starts moving from the rest
through 5 second . Calculate
………………………………………………………………………………………..
………………………………………………………………………………………..
2) A car moves at speed 100 m/sec
5 m /sec2
. Calculate the car’s speed
………………………………………………………………………………………..
………………………………………………………………………………………..
VI) Which of the graphs represents :
(A)
1- A body moves with regular speed.
2- A body moves with irregular speed.
1- A body at rest.
VII) The opposite graph represents the motion of car :
Which part represents the motion with.
1- Zero acceleration.
2- Negative acceleration.
3- Positive acceleration.
Distance Distance
Time
4
A body moves with acceleration equals zero.
………………………………………………………………………………………..
car starts moving from the rest. Then its speed increased to 90
Calculate the acceleration of the moving car .
………………………………………………………………………………………..
………………………………………………………………………………………..
ed 100 m/sec . if the driver reduces its speed by a rate of
the car’s speed after 12 seconds.
………………………………………………………………………………………..
………………………………………………………………………………………..
) Which of the graphs represents :
(B)
regular speed.
A body moves with irregular speed.
VII) The opposite graph represents the motion of car :
Which part represents the motion with.
Distance Distance
Time
………………………………………………………………………………………..
Then its speed increased to 90 m/s
the acceleration of the moving car .
………………………………………………………………………………………..
………………………………………………………………………………………..
if the driver reduces its speed by a rate of
………………………………………………………………………………………..
………………………………………………………………………………………..
(C)
Distance
Time

5
Lesson three
Physical Quantities scalars and vectors
I) Complete the following :
1. The distance is a ……..…… quantity while displacement is a …………. quantity .
2. ……...…… is the covered distance in a constant direction and is a vector quantity .
3. When a body moves in a straight line in one direction , its distance covered by the
body is ………….. its displacement .
II) What’s the difference between :
1-Distance and displacement ( Definition only ) .
………………………………………………………………………………………….
………………………………………………………………………………………….
2- Scalar quantity and vector quantity ( Definition and Examples ) .
…………………………………………………………………………………………
…………………………………………………………………………………………
III) What is meant by :
1. The displacement of on object is 60 meters in east direction .
………………………………………………………………………………………….
2. The average velocity of a moving car is 80 km /h
………………………………………………………………………………………….
IV) When dose the following cases happen :
1. The displacement covered by a moving body equals zero .
…………………………………………………………………………………………
2. The distance and displacement of a moving object are equal .
……………………………………………………………………………………………………..

6
V) Problem :
1- A tennis ball falls from a height of 30 m in 4sec. then it rebounds from the ground
to upward a distance of 5 m in 1sec . Find the distance covered by the ball and
the displacement then Calculate the average speed and velocity .
………………………………………………………………………………………..
………………………………………………………………………………………….
………………………………………………………………………………………….
2- If a body starts its motion from point (a) covered 20 meters northward till point (b)
within 20 seconds , then 50 meters eastward till point (c) within 10 seconds then
20 meters southward till point (d) within 5 seconds. Calculate
i) The average speed ii)The velocity
………………………………………………………………………………………….
………………………………………………………………………………………….
3- A body moves in a circular path , starting from the point A to B to C to D and
returns back to the start point (A) . If the circumference of the path is 200 meters
and the body covered the distance (ABC) within 10 seconds . then it covered the
distance (CDA) within 20 seconds. calculate :
a) The total distance the body moved.
………………………………………………………………………………………
b) The average speed of the body .
………………………………………………………………………………………
c) The displacement .
………………………………………………………………………………………
c) The velocity .
………………………………………………………………………………………

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4- A body moved from ( A ) to ( B ) into ( C ) as the drawing .
Therefore
1- The distance covered by the body = ………………………
2- Its displacement = ……………………………
3- The average speed = ……………………………
VI) Give reasons for :
1. Velocity and acceleration are vector quantities . while distance and length are
scalar quantities .
………………………………………………………………………………………..
………………………………………………………………………………………..
2. Pilots take in consideration the velocity of the wind .
………………………………………………………………………………………….
………………………………………………………………………………………….
VII) Write the scientific term :
1. The length of shortest straight line between primary position and final position .
[………………….……]
2. The rate of change of displacement . […………………….…]
3. The vector quantity which is measured in m/s2 .
[………………….……]
4. It is from the starting point towards the ending point [………………….……]
ab
c
60 m
80 m
4 s
6 s

8
Unit Two
Lesson one: Mirrors
I) Write the scientific term :
1.Rebounding of light to the same side when it strikes a reflecting surface .
[…………………….…]
2. The angle between the incident light ray and the perpendicular line on the
reflecting surface . [……………………….]
3. Angle of incidence = Angle of reflection . […………….…………]
4. The point of collection of parallel light rays to the principal axis of the concave
mirror . [………………………..]
5. Twice the focal length of a spherical mirror . [………………..………]
6. The distance between the center of curvature and any point on the reflecting
surface . [………………………..]
II) Put ( √ ) or ( × ) in front of the following statements and correct the false ones
1. If the distance between the object and a plane mirror is 3m , th the distance
between the object and its image is 3 m . ( )
2. When the angle between the incident ray and the plane mirror surface is 60º , so
the angle of reflection is 50º . ( )
3. The formed image for a body put in front of a convex mirror is virtual , inverted
and smaller . ( )
4. A spherical mirror of diameter equals 14 cm , its focal length is 6 cm .( )
5. The focus is the point that is in the middle of the reflective surface of the mirror .
( )

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III) : If a body is put in front of a plane mirror at a distance 8 meters , then it
moves toward the mirror for 1 meter .
-What is the distance between the body and its image in the first case?
- What is the distance between the body and its image in the second case?
IV) Give reasons for :
1. Concave mirror is used in cooking by using solar energy .
………………………………………………………………………………………….
………………………………………………………………………………………….
2. A convex mirror is put at the left side of the driver of the car .
………………………………………………………………………………………….
………………………………………………………………………………………….
3. The incident light ray falling perpendicular on a reflecting surface reflects on itself
………………………………………………………………………………………….
………………………………………………………………………………………….
4. The word “AMBULANCE” is written in a converted way on the ambulance car.
…………………………………………………………………………………………
…………………………………………………………………………………………
V) Show by drawing the path and the direction of rays in the following cases :
• An object in front of a concave mirror at a distance less than its focal length
( Determine the properties of the formed image )
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………

• The image that is formed by the convex mirror .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
• An object in front of a concave mirror at a distance of 7 cm . Knowing that its
focal length is 5 cm .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
VI) An object was put at a distance 20 cm from a mirror
a screen where its length equal to the
(1) What is the type of the mirror .
………………………………………………………………………………………….
(2) Calculate the focal length of the mirror .
………………………………………………………………………………………….
(3) Draw the path rays that shows the formation of this image .
……………………………………………………………………………………
…………………………………………………………………………………………
VII) Complete the drawing
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The image that is formed by the convex mirror .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
An object in front of a concave mirror at a distance of 7 cm . Knowing that its
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
put at a distance 20 cm from a mirror, the image is formed
equal to the object .
(1) What is the type of the mirror .
………………………………………………………………………………………….
(2) Calculate the focal length of the mirror .
………………………………………………………………………………………….
……………………………………………………………………………………
…………………………………………………………………………………………
drawing :
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
An object in front of a concave mirror at a distance of 7 cm . Knowing that its
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
the image is formed on
………………………………………………………………………………………….
………………………………………………………………………………………….
…………………………………………………………………………………………
…………………………………………………………………………………………

11
Lesson (2): Lenses
1. A point inside the lens on the principal axis in the mid distance between its faces is
……………………… .
2. The radius of the convex lens = 12 cm , Its focal length = …………… cm
3. The long sighted person needs a medical eye glasses with ………..……. Lenses .
4. The optical piece that forms an equal inverted image of the body is the …………..
5- The virtual image is formed by …………. or ……………. mirrors while it is
formed through ……….. lens.
1. The line joining between the two centers of curvature of the lens and passing
through the optical center . [………………………]
2. A vision defect results due to the formation of the image in front of retina .
[………………………]
3. The lenses that are used instead of glasses and can stick to the eye cornea .
[………………………]
4. A disease infects the eye lens , so it becomes dark . [………………………]
III) Give reasons for :
1. The convex lens has two foci , but the concave mirror has one focus .
…………………………………………………………………………………………
…………………………………………………………………………………………
2. The short–sightedness is treated by using a concave lens .
…………………………………………………………………………………………
…………………………………………………………………………………………

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3. It’s impossible to obtain a real image by using a concave lens .
…………………………………………………………………………………………
………………………………………………………………………………………..
4. The convex lens is called “converging lens” while the concave lens is called
“diverging lens” .
…………………………………………………………………………………………
…………………………………………………………………………………………
IV) What happens when :
1. A light ray is incident parallel to the principal axis of the convex lens .
…………………………………………………………………………………………
…………………………………………………………………………………………
2. The eye lens is too convex .
………………………………………………………………………………………..
3. A light ray passes through the optical center of the lens .
…………………………………………………………………………………………
…………………………………………………………………………………………
V) Define each of the following :
1. The lens .
………………………………………………………………………………………….
2. The center of curvature of the lens face .
…………………………………………………………………………………………
3. Short sight defect .
…………………………………………………………………………………………

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VI) Problem :
1. A concave lens has a focal length equals 3 cm . An object is placed at a distance of
4 cm . From the lens , determine the position of the formed mage and its properties
by drawing the light rays .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
2. A convex lens . its focal length equals 5 cm. An object is placed at a distance 7 cm
from the lens , Determine the position of the formed image and its properties by
drawing only two light rays .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
3. Mention the position and properties of the image formed of an object is put at a
distance less than the focal length .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
4. A convex lens with focal length of 20 cm an object was placed at a distance of 40
cm from the lens . Assign the distance of object’s image from the lens and
mention its properties .
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
VII)- Complete the following figures:

14
Unit Three
Lesson 1: The universe
1. The sun and eight planets revolving around it . […………………….]
2. It’s located in one of the spiral arms of the Milky way galaxy .
[…………….……….]
3.It contains all the stars we see at night in the sky . [……………………..]
4. The distance that is covered by light in one year . [……………………..]
5- The wide and extended apace that contains all galaxies , stars , planets and
everything [……………………..]
II) Give reasons for :
1. Our galaxy is called “ milky way” galaxy .
…………………………………………………………………………………………
…………………………………………………………………………………………
2. The continuous expansion of the space .
…………………………………………………………………………………………
…………………………………………………………………………………………
3. The gravity has important role in cosmogony of the universe .
…………………………………………………………………………………………
…………………………………………………………………………………………
III) Complete the following statements :
1. Each galaxy has a distinctive shape according to ……………. and …………. of the
groups of starts in universe .
2. The solar system is located in one of the spiral arms of …………..……. galaxy .

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3. Within minutes of the Big Bang , the atomic particles merged together producing
……………… and …………………….. .
4. The solar system contains a number of …..………… orbit the sun .
5. The sun takes about ……………. million years to complete one rotation around the
center of the galaxy .
6. Bigger units of the universe are ……………….
7. The gases that produces galaxies , stars and universe are ………..…. and
……………….

16
Lesson 2: The solar system
I) Complete the following :
1. The force of attraction between two objects is ………………… proportional to the
product of their masses and is ……………… proportional to the square of the
distance between them .
2. The …………….. rotates around the Earth in a fixed orbit and …………… rotates
around the sun once every Earthly day .
3. The scientist who established ……...………… theory is Laplace , but the scientist
who established the modern theory of the world is …………………….
4. The longest day is on …………….. where the shortest day is on ……….………
5. …………….. rotates around the sun once every 12 Earthly years .
1. The time taken by the planet to complete one rotation around its axis .
[…………..………]
2. A flat gaseous round disk that formed the solar system . […………………..]
3. The force that keeps the continuity of the planets rotation in their orbits around
the sun . [……………..……..]
4. The planet that has the shortest year on its surface . [……………………]
III) Correct the underline words :
1. The modern theory for formation of the solar system according to Laplace is due
to explosion of a star rotating around the sun .
2. The time of revolving Venus planet around its axis is one Earthly day .

17
3. The difference of day length from a planet to another is due to the speed of the
planet rotation around the sun .
IV) What would happen ?
1. When the distance between a planet and the sun increases .
…………………………………………………………………………………………
…………………………………………………………………………………………
2. Due to the difference in speed of planet rotation around its axis .
…………………………………………………………………………………………
…………………………………………………………………………………………
V) Explain the evolution of the solar system as the vision of the French scientist
“Laplace”
…………………………………………………………………………………………
…………………………………………………………………………………………
V)- Give reason for :
1- The day in Venus is longer that its year .
…………………………………………………………………………………………
…………………………………………………………………………………………
VI)- Discus the factors the affect :
- The length of the planet's day .
…………………………………………………………………………………………
………………………………………………………………………………………….
- The length of the planet's year .
…………………………………………………………………………………………
………………………………………………………………………………………….
- The gravitational force between two space bodies.
…………………………………………………………………………………………
………………………………………………………………………………………….

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Unit Four
Lesson 1: Cell Division
I) Put ( √ ) or ( × ) in front of the following statements and correct the false ones
1. The chromosome consists of a nucleic acid called RNA and protein. ( )
2. In the mitotic division , the spindle fibers are formed during interphase and
disappear in anaphase . ( )
3. The spindle fibers are formed in the plant cell from the centrosome . ( )
4. The nucleolus disappears through telophase of mitosis . ( )
5. Crossing over phenomenon occurs in the anaphase of first meiosis. ( )
II) Give reason for :
1. The nucleus is the part of the cell division .
…………………………………………………………………………………………
…………………………………………………………………………………………
2. Cellular division begins with interphase .
…………………………………………………………………………………………
…………………………………………………………………………………………
3. Crossing over is the source of genetic variation between members of the same
species .
………………………………………………………………………………………
………………………………………………………………………………………
III) Write the scientific term :
1- The phase in which the chromosomes are arranged at the middle of the cell during
the division […………………]
2. The point of connection of two chromatids together . […………............]
3. It contributes in genes exchanging between the chromosome’s chromatids and
distributing them in the gametes . [………………….]
4. A phase where some processes occur upon which formation of two cells each of
them contains chromosomes that equal in number with the parental cell […….....]

IV) If you have a plant that its cells have 20 chromosomes .
What is the number of chromosomes in the following cells ?
(1) leaf (2) ovum
(4) fertilized ovum (5) stem
V) From the following graphs answer the following questions
40 chromosomes
mother cell resulting cells
- Which graph represents mitosis
……………………………………………………………………………………….
- Which graph represents meiosis
……………………………………………………………………………………….
- What is the no. of the chromosomes in the resulting cells in each division .
…………………………………………………………………………………………
VI)- Name these stages of mitotic division:
19
What is the number of chromosomes in the following cells ?
(2) ovum (3) pollen grain
(5) stem (6) zygote
40 chromosomes
other cell resulting cells mother cell resulting cells
mitosis division ?
……………………………………………………………………………………….
Which graph represents meiosis division?
……………………………………………………………………………………….
What is the no. of the chromosomes in the resulting cells in each division .
…………………………………………………………………………………………
Name these stages of mitotic division:
grain
(6) zygote (7) root
40 chromosomes
resulting cells
……………………………………………………………………………………….
……………………………………………………………………………………….
What is the no. of the chromosomes in the resulting cells in each division .?
…………………………………………………………………………………………

20
Lesson 2: Sexual and asexual reproduction
1- A type of reproduction that occurs in the higher organisms. […………….…]
2- The ability of some animals to compensate their missing parts. [……………….]
3- It is formed as a result of the combination of the male gamete and the female
gamete . [……………….]
II) Give reasons for :
1. Spore propagation is a type of asexual reproduction which is common in some
fungi such as bread mould and mushroom .
…………………………………………………………………………………………
…………………………………………………………………………………………
2. The zygote has the same no . of chromosomes of cells of parental organism .
…………………………………………………………………………………………
…………………………………………………………………………………………
3. Starfish continues alive even a part of its body is cut .
…………………………………………………………………………………………
…………………………………………………………………………………………
4. Sexual reproduction is a source of the genetic variation .
…………………………………………………………………………………………
…………………………………………………………………………………………
III) Mention the importance of :
1. The sexual reproduction in concerning of the genetic structure .
……………………………………………………………………………………….
2. Vegetative reproduction .
……………………………………………………………………………………….

21
IV) What would happen :
1. separating a starfish arm , while it contains a part of the central disc .
…………………………………………………………………………………………
…………………………………………………………………………………………
2. Fusion of sperm with an ovum .
…………………………………………………………………………………………
…………………………………………………………………………………………
V) How does each of the following organisms reproduces
( if it is asexually reproduction , mention its typ )
1- sponge : ………………………. 2- man: ………………………………..
3- Bacteria:………………………. 4- Hydra: ……………………………..
5- Bread mould:…………………. 6- Paramecium: ………………………
7- starfish :………………………..
8- Plants ( with no need of seeds ): …………

22
Model exam
Question [ 1 ] A) Write the scientific term :
1- The point of the collection of the parallel light rays after being reflected from the
concave mirror . [……………………..]
2- The length of the shortest straight line between two positions . [……………………..]
3- The image that can be received on a screen . [……………………..]
4- The speed of a moving object relative to an observer . [……………………..]
B) In the opposite figure : C
A body starts its motion from point (A) to the west into (B)
to cover 12 meters through 5 seconds then it moves to the 16m 20 m
north into ( C ) to cover 16 meters through 9 seconds .
Calculate :
1- The total distance . 2- Average velocity
C) Give one use ( at least ) for each of the following :
1- A convex mirror. 2- The speedometer .
Question [ 2 ] A) Complete the following statements :
1- ………………….. is the straight line that passes through the center of curvature and
any point on the reflecting surface except the pole .
2- The result of dividing the total distance that a moving object covers by the total time
taken to cover this distance = ……………………………………
3- The measuring unit of the displacement is ……………………..
4- …………………..and ………………….. are the two factors necessary for the
description of motion .
5- When a person moves towards a plane mirror for 2 meter , the distance between his
body and the image decreases by ………………… meters .
6- ………………….. is the physical quantity that has magnitude only .
B) What is meant by :
1- Light reflection . 2- Radius of curvature = 12 cm
3- A moving train covers 100 kilometers in two hours .
B 12 m A

23
Question [ 3 ] A) Put (√ ) or ( × ) :
1- Mass , energy and force are considered as examples of vector physical quantities . ( )
2- When the body moves with a uniform acceleration , it means that it covers equal
Distances at equal periods of time . ( )
3- The body that moves with speed 90 km/H is faster than that moves with speed
25 m/second . ( )
4- The reflected light ray is the ray that falls on the reflecting surface . ( )
5- Pole of the mirror is a mid point on the reflecting surface of the spherical mirror. ( )
B) What is meant by the following graphs :
speed (m/sec) distance (m) speed (m/sec)
T(sec) T(sec) T(sec)
1)………………….. 2)……………………. 3)…………………….
C) Show by drawing:
The path of light rays of the formed image for an object in front of a concave mirror at a
distance less than double of focal length but more than focal length .
( Determine the properties of the formed image ) .
Question [ 4 ] A) Choose the correct answer :
1- A car moves with speed 100 m/sec , if the driver reduces its speed by the rate -3 m/sec2
, the car’s speed after 20 seconds equals …………… m/sec.
a) 160 b) -40 c) 40 d) 60
2- If the angle between the incident light ray and the reflecting surface is 40° , then the
angle of reflection = ………………….
a) 40° b) 50° c) 90° d) 150°
3- ……………… is the change of an objects position as the time passes according to the
position of another object .
a) Displacement b) Speed c) Acceleration d) Motion
4- When a body of height 6 cm is put at a distance 14 cm in front of a convex mirror of
radius 20 cm , the height of its image will be ………….. cm
a) 4 b) 8 c) 6 d) no correct answer
b) Complete the following drawings :
1) …………………………….. 2) ……………………………..
C FC F

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