Mokatam International Language School
Second Trimester
Revision Pack
Science
Grade 9
2023/2024
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
1
Questions
Multiple Choice
1) Any motion that repeats at regular time intervals is called
a. frequency.
b. Periodic motion.
c. Periods.
d. friction.
2) When a drill is used to bore a hole in an object,
a. no useful work is done.
b. no energy is lost due to friction.
c. the drill is 100 percent efficient.
d. friction causes the object to heat up.
3) Why does liquid rise in a thermometer?
a. convection
b. thermal expansion
c. condensation
d. radiation
4) To heat 1 g of water by 1 °C requires
a. 1 calorie.
b. 1 kilocalorie,
c. 1 joule.
d. 1 watt.
5) The best thermal insulators
a. conduct heat well.
b. are gases.
c. are metals.
d. have free electrons.
6) A region of space produces magnetic forces
a. Electric field.
b. Magnetic field.
c. Electromagnetic field.
d. Radiation.
7) The ……………. of a wave is the maximum displacement of the medium from its rest position?
a. Radiation.
b. Wavelength.
c. frequency.
d. Amplitude.
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
2
8) Energy added to a system
a. does work or increases thermal energy.
b. cannot heat the environment.
c. is converted to radiation.
d. reduces the kinetic energy of the system.
9) All engines operate at less than 100 percent efficiency because they
a. absorb heat.
b. conduct heat,
c. burn gasoline
d. emit heat
10) …………….. is a disturbance in matter that carries energy from one place to another.
a. Mechanical waves
b. Longitudinal waves
c. Transverse waves
d. Surface waves
11) In a transverse wave, the medium vibrates
a. at right angles to the wave direction.
b. in the same direction as the wave.
c. in a direction opposite that of the wave.
d. at a 45° angle to the wave direction.
12) The transfer of energy by electromagnetic waves traveling through matter or across space is called
a. Convection.
b. frequency.
c. Electromagnetic radiation
d. Conduction.
13) Which of the following is NOT true about mechanical waves?
a. They carry energy.
b. They transfer matter.
c. They can be longitudinal.
d. They require a medium.
14) ……………is a wave that travels along a surface separating two media.
a. Mechanical waves
b. Longitudinal waves
c. Transverse waves
d. Surface waves
15) The longer the tubing of an instrument, …………….
a. the Shorter is the wavelength of the standing wave, and the lower is the frequency of the note produced.
b. the longer is the wavelength of the standing wave, and the higher is the frequency of the note produced.
c. the longer is the wavelength of the standing wave, and the lower is the frequency of the note produced.
d. No correct answer.
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
3
16) ……………is the bending of a wave as it moves around an obstacle or passes through a narrow opening.
a. Reflection
b. Refraction
c. Interference
d. Diffraction
17) ……………is the number of complete cycles in a given time.
a. frequency
b. Periods
c. Wavelength
d. Surface waves
18) ……………occurs when two or more waves overlap and combine together.
a. Reflection
b. Refraction
c. Interference
d. Diffraction
19) ……………is the rate at which a wave’s energy flows through a given area.
a. Intensity
b. Speed
c. Wavelength
d. Surface waves
20) ……………is the frequency of a sound as you perceive it.
a. frequency
b. Pitch
c. Loudness
d. Intensity
Section 2 Complete:
1) ……….. is a type of heat transfer with no overall transfer of matter.
2) Materials that allow heat energy to pass through them are called ……………… while materials that do not
allow heat to pass through them are called ……………..
3) when wavelength is shorter, crests are ………………
4) Measuring the average kinetic energy of the particles in an object due to their random motions through space
is ………
5) ……………… occurs when a wave bounces off a surface that it cannot pass through, while ……… is the
bending of a wave as it enters a new medium at an angle.
6) A ………….. wave is a wave in which the vibration of the medium is parallel to the direction the wave
travels, but a ………….. wave is a wave in which the vibration of the medium is perpendicular to the direction
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
4
the wave travels
7) According to the 2nd law of thermodynamics, …………. is any device that converts heat into work.
8) Radiation is the transfer of energy by waves moving through ……………………..
9) For a………………. , wavelength is measured between adjacent crests or between adjacent troughs. For a
……………….. , wavelength is the distance between adjacent compressions or rarefactions.
10) …………….. is a point on a standing wave that has no displacement from the rest position, while
…………….. is a point where a crest or trough occurs midway between two nodes.
11) Sound intensity is measured using ………………
12) Humans can hear sounds from ………… to …………… Hz
13) Instruments produce different frequencies by ………………………
14) Magnetic fields are produced by ………., by …………….. , and by ……………
Section 3 Put () or (×)
1) Sound waves travel fastest in solids, slower in liquids, and slowest in gases.
(
2) Metals are very good thermal insulators.
(
)
3) The third law of thermodynamics states that absolute zero can be reached.
(
)
4) Convection is a way to transfer heat energy in solids.
(
)
)
5) Electromagnetic waves are transverse waves consisting of changing electric fields and changing magnetic
fields..
( )
6) Measuring unit of specific heat is Joules.
(
)
7) Waves in springs are examples of longitudinal waves.
(
)
8) Sound waves are transverse waves.
9) Measuring unit of frequency is Hertz.
10) Reflection changes the speed or frequency of a wave
(
(
)
)
(
)
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
5
Section 4 Answer the following:
1) One end of a rope is vibrated to produce a wave with a wavelength of 0.25 meters. The frequency of the
wave is 3.0 hertz. What is the speed of the wave?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
2) Why are metals good conductors?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
3) Why does an object filled with air expand when it is heated?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
4) Compare between constructive and destructive interference?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
5) How can humans hear?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
6) How is the sound reproduced?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
7) Why intensity decreases on moving away from the light source?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
8) Why does a piece of steel heat up more than an equal mass of plastic when both absorb the same energy ?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
6
9) How does sunlight reach an astronaut on the International Space Station?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
10) What is waste heat
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
11) How are some surface waves similar to both transverse and longitudinal waves?
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
7
Answers
Choose the correct answer
1
A
2
D
3
A
4
A
5
B
6
B
7
D
8
9
10
11
12
C
13
14
15
C
16
D
17
A
18
C
19
A
20
B
Complete the following
1
2
3
Closer together
4
5
Reflection - Refraction
6
7
8
9
transverse wave - longitudinal wave
10
Node - antinode
11
Decibels (dB)
12
20 to 20,000
13
changing the length of tubing through which air moves
14
Magnets – changing electric fields - vibrating charges
15
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
8
Put () or (×)
1
2
3
4
5
6
7
8
9
10


×

×
Answer the following
1
Speed = wave length × frequency = 0.25 × 3 = 0.75 m/s
2
As they have free moving electrons and ions
3
Because by heating, temperature increase, increasing the K.E of particles, more collisions
happen increasing gas pressure and making the object expands.
4
5
The outer ear gathers and focuses sound into the middle ear, which receives and amplifies the
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
9
vibrations. The inner ear uses nerve endings to sense vibrations and send signals to the brain.
6
Sound is recorded by converting sound waves into electronic signals that can be processed and
stored. Sound is reproduced by converting electronic signals back into sound waves.
7
As waves travel away from the source, they pass through a larger and larger area
8
As steel has lower specific heat than plastic
9
Through radiation
10
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
10
Vision: Mokatam International Language School encourages the development of the whole student. Our
aim is to support learners in becoming curious, reflective and critical in their thinking as global citizens
11