KUULCHAT
SCIENCE MOCK
OBJECTIVE TEST
1.
How much work is done when a kerosene tin is pushed with a force of 20 N through a distance of 2 m?
A.
0.01 J
B.
0.10 J
C.
10.0 J
D.
20.0 J
E.
40.0 J
Answer: E
Work done = Force x Distance
Force = 20 N
Distance = 2 m
Work done = 20 N x 2 m = 40 J
2.
Alum is added to water during treatment to
A.
kill germs.
B.
help suspended particles to settle.
C.
make the water colourless.
D.
give taste to the water.
Answer: B
3.
Boiling and chlorination are used in water purification to
A.
kill germs.
B.
help suspended particles to settle.
C.
remove suspended particles.
D.
remove hardness of the water.
Answer: A
4.
Chlorine gas is an example of
A.
an atom.
B.
an element.
C.
a compound.
D.
a molecule.
Answer: D
5.
Leaching of nutrients from the soil leads to soil
A.
acidity.
B.
alkalinity.
C.
erosion.
D.
porosity.
Answer: C
6.
The space occupied by matter is its
A.
area
B.
length
C.
radius
D.
width
E.
volume
Answer: E
7.
Which of the following habits will help in the control of diseases contracted through air?
I. Not throwing human wastes into rivers
II. Washing of hands after visiting the toilet
III. Not spitting about in public places
IV. Keeping foods always covered
A.
I and II only
B.
II and III only
C.
III only
D.
I, II and IV only
Answer: B
8.
When living organisms die, the mineral salts in their bodies become available to the soil through the process of
A.
evaporation
B.
sedimentation
C.
defecation
D.
decay
E.
osmosis
Answer: D
9.
What do human beings obtain from food to enable them work?
A.
Blood
B.
Energy
C.
Vitamins
D.
Proteins
E.
Minerals
Answer: B
10.
Which of the folloeing substances are carried by the blood?
I. Nutrients
II. Urine
III. Oxygen
IV. Carbon dioxide
A.
II and III only
B.
I, II and IV only
C.
I and III only
D.
I, III and IV only
Answer: D
11.
A cylinder metal has radius 7 cm and height 2 cm. Determine the volume of the cylinder.
[Take π = ]
A.
44 cm3
B.
107 cm3
C.
308 cm3
D.
1078 cm3
Answer: C
Volume of a cylinder
Volume = πr2h
Where r = radius of the base of the cylinder
h = height of the cylinder
r = 7 cm
h = 2 cm
π =
r2 = r x r
Volume = x 7 cm x 7 cm x 2 cm
Note: the denominator 7 cancels on of the 7s multiplying.
Volume = 22 x 1 cm x 7 cm x 2 cm
Volume = 308 cm3
12.
An aluminium cube of side 2 m has a mass 24 kg. Determine the density of the aluminium.
A.
3 kg m-3
B.
12 kg m-3
C.
24 kg m-3
D.
48 kg m-3
Answer: A
Density = Mass / Volume
Volume = Length x Breadth x Height
Breadth = Height = Length for cube
Volume of a cube = Length x Length x Length = Length3
Volume of the aluminium = 23 = 2 x 2 x 2 = 8 m 3
Density = 24 kg/ 8 m 3 = 3 kg m-3
13.
Which of the following is a liquid?
A.
Iron
B.
Mercury
C.
Brass
D.
Gold
E.
Aluminium
Answer: B
14.
The function of the platelets in the circulatory system of humans is to
A.
transport oxygen.
B.
transport carbon dioxide.
C.
defend the body.
D.
cloth the blood.
Answer: D
15.
The function of the lungs is to
A.
maintain a constant amount of water in the body.
B.
absorb oxygen from the blood.
C.
absorb carbon dioxide from the blood.
D.
maintain the temperature of the body constant.
Answer: C
How the lungs work
Every cell in your body needs oxygen to live. The air we breathe contains oxygen and other gases. The respiratory system's main job is to move fresh air into your body while removing waste gases.
Once in the lungs, oxygen is moved into the bloodstream and carried through your body. At each cell in your body, oxygen is exchanged for a waste gas called carbon dioxide. Your bloodstream then carries this waste gas back to the lungs where it is removed from the bloodstream and then exhaled. Your lungs and respiratory system automatically perform this vital process, called gas exchange.
16.
A bottle of water removed from a refrigerator soon becomes covered with droplets of water because the
A.
bottle is porous.
B.
bottle is full of water.
C.
water in the surrounding atmosphere is colder than the water in the bottle.
D.
water in the surrounding atmosphere is warmer than the water in the bottle
Answer: D
17.
The process of fusion of sperm and ovum is known as
A.
fertilization
B.
menstruation
C.
pollination
D.
reproduction
E.
lactation
Answer: A
18.
The consequences of the greenhouse effect on humans include
I. flooding of coastal cities
II. desertification of fertile areas
III. increased number of storms
IV. increased use of fossil fuels
A.
I, II, III and IV
B.
II and III only
C.
I, II and III only
D.
I and II only
Answer: D
19.
The parasite that is found on dogs is
A.
capsid.
B.
guinea worm.
C.
plasmodium.
D.
tapeworm.
E.
Tick.
Answer: E
20.
The efficiency of a machine is given by the ratio
A.
B.
C.
D.
E.
Answer: E
21.
The method used to separate an insoluble solid from a liquid is
A.
crystallization.
B.
distillation.
C.
filtration.
D.
sublimation.
Answer: C
FILTRATION
22.
In what units are work and energy measured?
A.
work in joules, energy in watts
B.
work in joules, energy in joules
C.
work in newtons, energy in joules
D.
energy in watts, work in watts
E.
energy in newtons, work in joules
Answer: B
23.
When a person jumps up, he/she is able to come down because of the
A.
pull of the earth's gravitational force.
B.
pull of the earth's magnetic force.
C.
resistance of the earth's atmosphere to the upward motion.
D.
pressure of the earth's atmosphere on the person.
Answer: A
24.
Capillary action is applied in the following activities except
A.
blotting an ink with a blotting paper.
B.
absorption of water with a towel.
C.
rising of water in a very narrow glass tube.
D.
sticking of water droplets on the surface of a glass tube.
Answer: D
Capillary action is the process of a liquid flowing in a narrow space without the assistance of, or even in opposition to, any external forces like gravity.
25.
Which of the following devices is made of semiconductor?
A.
Capacitor
B.
Inductor
C.
Resistor
D.
Transistor
Answer: D
26.
The following products, X,Y,Z and W have masses 0.05 kg, 50 mg, 500 g and 0.05 g respectively.
Use this information to answer the question below.
Which of the products have the same mass?
A.
Y and W
B.
X and Y
C.
Y and Z
D.
X and W
Answer: A
Convert all the masses to the same unit and pick the product with the highest mass.
Let's change all the masses to grams (g)
To change kilogram (kg) to gram, you must multiply by 1000
To change milligram (mg) to gram, you must divide by 1000
Product X mass = 0.05 kg = 0.05 x 1000 g = 50 g
Product Y mass = 50 mg = = 0.05 g
Product Z mass = 500 g
Product W mass = 0.05 g
Product Y and W have the same mass, 0.05 g.
27.
Which of the following practices will destroy the breeding grounds of mosquitoes?
A.
Sleeping in mosquito nets
B.
Spraying with insecticides
C.
Using insect repellent
D.
Introducing fish into ponds
E.
Burying all empty cans
Answer: B
28.
The figure below shows a simple electric circuit.
Use it to answer the question below.
The purpose of the component labelled IV is to
A.
supply energy to the circuit.
B.
measure the voltage of the battery.
C.
prevent too much current from flowing.
D.
close the circuit.
Answer: C
29.
The food nutrient which ensures good health in farm animals is
A.
carbohydrates.
B.
minerals.
C.
proteins.
D.
vitamins.
Answer: D
30.
The three states of matter are
A.
Water, liquid and gas
B.
Earth, liquid and gas
C.
Solid, liquid and air
D.
Gas, earth and water
E.
Gas, liquid and solid
Answer: E
31.
Digested food substances are absorbed into the blood stream in the
A.
kidneys.
B.
liver.
C.
stomach.
D.
ileum.
Answer: D
32.
The type of management system which allows farm animals to roam about freely is known as
A.
extensive system.
B.
intensive system.
C.
semi-extensive system.
D.
semi-intensive system.
Answer: A
33.
Which of the following waste disposal practices is best for plastic disposal?
A.
Burning
B.
Composting
C.
Incineration
D.
Recycling
Answer: D
34.
The digestion of carbohydrates starts in the
A.
mouth
B.
throat
C.
stomach
D.
duodenum
E.
ileum
Answer: A
35.
Human beings are omnivorous because they eat
A.
both cooked and raw food.
B.
only flesh.
C.
only fruits.
D.
both plants and animals.
Answer: D
Types of feedings
Carnivore: the eating of animals.
Herbivore: the eating of plants.
Omnivore: the eating of both plants, animals, fungi, bacteria etc.
36.
Electricity is used by appliances to do work. This means that electricity is a form of
A.
energy.
B.
force.
C.
generator.
D.
machine.
Answer: A
Energy is define as the ability to do work. Electricity is a form of energy (Electrical Energy).
37.
The practice of growing cowpea and maize on a piece of land at the same time is known as
A.
mixed farming.
B.
mixed cropping.
C.
land rotation.
D.
crop rotation.
Answer: B
Mixed Cropping
When two or more crops are grown on the same land simultaneously (at the same time), it is known as mixed cropping
Mixed Farming
Growing crops as well as livestock, animal husbandry,etc all on same farm or land.
Crop Rotation
The practice of planting different crops across a sequence of growing seasons on the same plot of land to improve soil health, optimize nutrients in the soil, and combat pest and weed pressure.
38.
Which of the following processes removes carbon from the atmosphere?
A.
Respiration
B.
Burning
C.
Decomposition
D.
Photosynthesis
Answer: D
Respiration
The chemical breakdown of organic food substances such as glucose in the living cells to release energy with or without molecular oxygen.
Burning
Combustion, or burning,is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke.
Decomposition
The process or effect of simplifying a single chemical entity into two or more fragments.
Photosynthesis
Photosynthesis is the process by which green plants manufacture food (starch/glucose) using carbon dioxide and water in the presence of sunlight and chlorophyll.
39.
The farm animal which has crop as part of its digestive system is the
A.
fowl.
B.
goat.
C.
pig.
D.
sheep.
Answer: A
40.
Which of these is not a sense organ?
A.
Eye
B.
Ear
C.
Nose
D.
Skin
E.
Heart
Answer: E
THEORY QUESTIONS
1.
(a)
Define the following terms and give one example of each:
(i)
Element
(ii)
Mixture
(iii)
Compound
(b)
Explain the following terms:
(i)
Work
(ii)
Energy
(c)
State the units in which each of the following are measured:
(i)
Power
(ii)
Energy
(iii)
Electric current
(iv)
Temperature
(d)
A body of mass 100 kg is placed at a point 2 m above the ground. What is the potential energy of the body with reference to the ground?
[Take g = 10 ms-2]
(e)
State three characteristics of each of the following:
(i)
An insect pollinated flower
(ii)
A wind pollinated flower
(a)
(i)
An element is a substance that cannot be broken down/split into simpler substances by any known chemical means.
Examples of elements (First 20 elements)
| Atomic Number | Element | Symbol |
| 1 | Hydrogen | H |
| 2 | Helium | He |
| 3 | Lithium | Li |
| 4 | Beryllium | Be |
| 5 | Boron | B |
| 6 | Carbon | C |
| 7 | Nitrogen | N |
| 8 | Oxygen | O |
| 9 | Fluorine | F |
| 10 | Neon | Ne |
| 11 | Sodium | Na |
| 12 | Magnesium | Mg |
| 13 | Aluminium | Al |
| 14 | Si | Silicon |
| 15 | Phosphorus | P |
| 16 | Sulphur | S |
| 17 | Chlorine | Cl |
| 18 | Argon | Ar |
| 19 | Potassium | K |
| 20 | Calcium | Ca |
(ii)
Mixture is what is formed when two or more substances are put together/combine physically.
Examples of mixtures
1. Air
2. Salt solution
3. Sugar solution
4. Common salt and sand mixed together
5. Muddy water
6. Alcohol and water mixed together
7. Powdered charcoal and iron filings mixed together
8. Powdered chalk and water mixed together
9. Iodine and sand mixed together
10. Sodium chloride/common salt and sand mixed together
11. Sawdust and iron filings mixed together
12. Powdered charcoal and water mixed together
13. Brass
14. Bronze
(iii)
A compound is the substance formed as a result of the chemical combination of two or more elements.
OR
A compound is a substance which is made up of two or more elements chemically combined.
Examples of compounds
1. Water/H2O
2. Common salt/Sodium chloride/NaCl
3. Carbon dioxide/CO2
4. Ammonia/NH3
5. Cupric oxide/Copper (II) oxide/CuO
6. Sulphuric acid/H2SO4
7. Sodium hydroxide/NaOH
8. Ammonium chloride/NH4Cl
9. Hydrochloric acid/HCl
10. Copper (II) sulphate/Copper (II) tetraoxosulphate (VI)/CuSO4
11. Iron (II) chloride/FeCl3
12. Magnesium chloride /MgCl2
13. Iron (II) sulphide/FeS
14. Ammonium hydroxide/NH4OH
15. Calcium carbonate/CaCO3
16. Calcium chloride/CaCl2
17. Silver chloride/AgCl
18. Sodium tetraoxosulphate (VI)/Na2SO4
19. Sodium nitrate/Sodium trioxonitrate (V)/NaNO3
20. Potassium sulphate/Potassium tetraoxosulphate (VI)/K2SO4
(b)
(i)
Work is said to be done when an application of a force moves an object through a distance in the direction of the force
OR
Work is said to be done when a force moves a body through a distance in the direction of the force.
(ii)
Energy is the ability to do work.
(c)
Units of measurement:
(i)
Power → Watts (W)
(ii)
Energy → Joules (J)
(iii)
Electric current → Amperes (A)
(iv)
Temperature → Kelvin (K)/Degree celsius (°C)
(d)
Potential energy = Mass (m) x Acceleration due to gravity (g) x Height (h)
Mass (m) = 100 kg
Acceleration due to gravity (g) = 10 ms-2
Height (h) = 2 m
Potential energy = 100 kg x 10 ms-2 x 2 m
Potential energy = 2000 J
(e)
i)
Characteristics of an insect pollinated flower
1. Petals are large
2. Petals are brightly coloured
3. The flower is usually scented
4. The flower has nectar
5. Stigma is inside the flower
6. Stigma is compact and sticky
7. Pollen grains produced per anther are few
8. Pollen grains are sticky, large, rough and heavy
9. Filaments are short and stout
ii)
Characteristics of a wind pollinated flower
1. Have less brightly coloured petals/petals are dull in colour
2. Petals are small in sizes and not easily seen or absent
3. The flower lacks nectar
4. The flower is not scented
5. Large amount of pollen grains are produced per anther
6. Have feathery/hairy stigma
7. Stigma hangs down to be able to catch pollen grains floating in the air
8. Pollen grains are small, light or dry and smooth
9. Filaments are long and flexible
2.
a)
i)
Differentiate between egestion and digestion in nutrition.
ii)
What is the end-product of digestion?
b)
Give one example of a chemical compound used in:
i)
medicine;
ii)
agriculture;
iii)
industry.
c)
i)
Define the term soil profile.
ii)
State two ways in which soil profile is important in crop production.
d)
i)
State two steps used by scientists in doing their work.
ii)
Give two subjects that may be considered as applied sciences.
a)
i)
Differences between egestion and digestion in nutrition
Egestion is the removal of undigested food/semi-solid or waste/faeces from the anus while digestion is the breaking down of food into smaller building blocks or components that can be absorbed into the blood stream.
ii)
End-products of digestion
1. Glucose/simple sugar
2. Amino acids
3. Fatty acids and glycerol
4. Final results obtained after breakdown of complex food substances
b)
Examples of chemical compound used in:
i)
Medicine
Drugs or other pharmaceutical products
Examples: Paracetamol, alcohol, milk of magnesia, aspirin, etc.
ii)
Agriculture
1. Insecticides
2. Pesticides
3. Fertilizers
iii)
Industry
1. Hydrochloric acid
2. Sodium chloride
3. Ammonia
4. Ethanol
5. Nitric acid
6. Sulphuric acid
7. Sodium Hydroxide
c)
i)
Soil profile is the vertical section of the land showing the various horizons or layers and their composition.
ii)
Importance of soil profile in crop production
1. Helps to know the type of tools to choose
2. Helps to select good soil for the crop
3. Helpts to determine depth at which tillage implements must be set
4. Helps to know soil management practices to adopt
5. Helps to determine the type of fertilizer to use or apply
6. Helps to determine the type of crop to grow
7. Helps to know the water holding capacity of the soil
8. Helps to determine fertility of soil
d)
i)
Steps used by scientists to do work
1. Identifying problem
2. Observing
3. Hypothesis
4. Collection of data
5. Experimenting
6. Analyzing data
7. Drawing conclusion
ii)
Subjects considered as applied science
1. Engineering
2. Medicine
3. Agriculture
4. I.C.T
5. Pharmacy
6. Electronics
3.
(a)
Name two:
(i)
animal products used in preparing protein-rich feed for poultry;
(ii)
plant produces used in preparing carbohydrate-rich feed for poultry.
[4 marks]
(b)
Describe briefly the water cycle.
[6 marks]
(c)
Consider the following mixtures:
Air, vinegar.
Air is essential to life.
Vinegar is a common household substance.
(i)
Name the two major components of each mixture.
(ii)
Which of the components named in (i) acts as the solvent in each of the mixtures?
[6 marks]
(d)
(i)
State two reasons why there is no life on the planet Jupiter.
(ii)
List two other outer planets without life.
[4 marks]
(a)
(i)
Animal products used in preparing protein-rich feed for poultry
1. Feather meal
2. Blood meal
3. Fish meal
4. Milk by-products
5. Meat meal
Any 2 x 1 mark = 2 marks
(ii)
Plant produces used in preparing carbohydrate-rich feed for poultry
1. Sorghum
2. Millet
3. Maize
4. Wheat
5. Rice
6. Wheat bran
Any 2 x 1 mark = 2 marks
(b)
The water cycle
Water evaporates from water bodies into the atmosphere (1 mark) where it condenses into the clouds (1 mark) and falls back into the earth's surface as rain (precipitation) (1 mark).
This then flows into water bodies (1 mark) and taken up by plants (1 mark) which transpire to give water vapour (1 mark).
6 marks
(c)
(i)
Vinegar → ethanoic acid (1 mark) and water (1 mark)
2 marks
Air → nitrogen (1 mark) and oxygen (1 mark)
2 marks
(ii)
Vinegar → water is the solvent (1 mark)
Air → nitrogen is the solvent (1 mark)
2 marks
(d)
(i)
Reasons why there is no life on the planet Jupiter
1. Extreme/cold temperatures
2. No oxygen
3. No water
4. Far away from the sun
5. Absence of solid surface
6. Toxic radiations/gases
7. Strong magnetic field
Any 2 x 1 mark = 2 marks
(ii)
Other outer planets without life
1. Saturn
2. Uranus
3. Neptune
Any 2 x 1 mark = 2 marks
4.
(a)
(i)
What is soil erosion? Give two types of soil erosion
(ii)
Give three activities of man that can cause soil erosion.
(iii)
List three ways by which soil can be conserved.
(b)
(i)
What is a lever?
(ii)
Classify the following under first class, second class and third class levers.
Sugar tong
Bottle opener
Paper cutter
A pair of scissors
Fishing rod
Claw hammer
(c)
In each of the following activities, state whether the changes that occurred are:
(i)
physical or chemical
(ii)
reversible or irreversible
I.
Some boiled cassava and plantain were pounded together into fufu.
II.
A piece of ice block is put in a cup. After a while, it is found out that the block had changed into a liquid
III.
A clean piece of nail was put into a beaker of water. After five days it was observed that the colour of the nail had changed.
(a)
(i)
Soil erosion is the removal/washing away of soil particles/topsoil by running water or rain or wind.
Types of soil erosion
1. Gully
2. Rill
3. Sheet
4. Splash
(ii)
Activities of man that can cause soil erosion
1. Road construction
2. Bush fires
3. Deforestation
4. Farming/over-cropping
5. Sand wining/soil removal for building and road construction
6. Over-grazing by farm animals
(iii)
Ways by which soil can be conserved
1. Cover cropping
2. Crop rotation
3. Green manuring
4. Fertilizer application
5. Liming
6. Composting
7. Mixed farming
8. Mixed cropping
9. Alley cropping
10. Mulching
11. Bush fallowing
12. Application of farm yard manure/kraal manure/poultry manure
13. Use of leguminous crops to fix nitrogen
14. Tillage to improve aeration
15. Irrigation
16. Afforestation and reafforestation
17. Land rotation
18. Contour ploughing
19. Erecting windbreaks
(b)
(i)
A lever is a simple machine which consists of a rigid bar/rod free to turn about a fixed turning point called the fulcrum/pivot.
(ii)
Classes of levers
| First class lever | Second class lever | Third class lever |
|
A pair of scissors
|
Bottle opener
|
Sugar tong
|
(c)
| # | Activity | Change | Reversible or irreversible |
| I. | Some boiled cassava and plantain were pounded together into fufu. | Physical change | Irreversible |
| II. | A piece of ice block is put in a cup. After a while, it is found out that the block had changed into a liquid | Physical change | Reversible |
| III. | A clean piece of nail was put into a beaker of water. After five days it was observed that the colour of the nail had changed. | Chemical change | Irreversible |
5.
(a)
(i)
Explain the term balanced diet.
(ii)
Name any two classes of food which should be present in a balanced diet.
(iii)
Give one function of each class of food named in (a) (ii) above.
(b)
An object is placed in front of a pinhole camera as shown in the diagram below:
Draw in your answer book a ray diagram (not to scale) to show how the image is formed on the screen of the camera.
(c)
State the two laws of reflection of light
(d)
(i)
Describe how ions are formed from atoms.
(ii)
State two differences between a proton and an electron.
(a)
(i)
Balanced diet is a diet that contains all the essential food nutrients in the right proportions.
(ii)
Classes of food which should be present in a balanced diet
1. Carbohydrates
2. Proteins
3. Fats and oils
4. Vitamins
(iii)
Protein helps to build and repair the worn out tissues in the body
Carbohydrate gives the body the energy it needs
Fats and oils provide energy for the body
Vitamins protect the body from diseases
(b)
(c)
Laws of reflection
1. The incident ray, the reflected ray and the normal at the point of incidence all lie in the same plane
2. The angle of incidence is equal to the angle of reflection
(d)
(i)
How ions are formed from atoms
1. Ions are formed when an atom gains or loses an electron
2. When an atom gains an electron, the number of electrons becomes greater than the number of protons and so a negative ion (Anion) is formed
3. When an atom loses an electron, the number of protons becomes greater than the number of electrons and so a positive ion (Cation) is formed
(ii)
Differences between a proton and an electron
| Proton | Electron |
| Has positive charge | Has negative charge |
| Is located inside the nucleus | Is located outside the nucleus |
| Is more massive/heavier/denser | Is less massive/lighter |
6.
(a)
Explain why a tomato plant is likely to wilt if too much fertilizer is applied to it.
(b)
(i)
Give two differences between electrical insulators and electrical conductors.
(ii)
State two effects of illegal electrical connections in the home.
(c)
Explain each of the following terms as used to describe change of state of matter:
(i)
condensation;
(ii)
freezing.
(d)
(i)
State two diseases of the circulatory system in humans.
(ii)
Mention two ways in which each of the diseases you have stated in (d)(i) can be prevented.
(a)
Why a tomato plant is likely to wilt if too much fertilizer is applied to it
Once two solutions of different concentrations come into contact, water molecules will flow from low to higher concentrated solution. Hence application of fertilizer makes the soil solution of higher concentration so water flow out of the plant by osmosis. The tomato plant plasmolyses/loses water and wilt.
Note
Plasmolysis describes a process involving a plant cell losing water content and therefore contracting and shrinking its cytoplasm and plasma membrane away from the inside of its cell wall. This occurs if the solution surrounding a plant cell is hypertonic or has a high concentration of solutes like salt.
(b)
(i)
Differences between electrical insulators and electrical conductors
| Electrical insulators | Electrical conductors |
| Does not conduct electricity | Conducts electricity |
| Has narrow conduction energy band | Has wide conduction energy band |
| There exists a wide forbidden energy gap between valence and conduction band | Has no forbidden energy gap |
| Electrons firmly bound to nucleus | Electrons loosely bound to nucleus |
| There are no free electrons | Has more free electrons |
(ii)
Effects of illegal electrical connections in the home
1. Overload of power supply
2. Drop in voltage of electricity
3. Leads to frequent power cuts
4. Leads to electrocution/electric shock
5. May cause fire outbreak
6. May damage electrical appliances
7. Leads to loss of revenue to government
(c)
(i)
Condensation is the change from the gas state to the liquid state.
(ii)
Freezing is the change from the liquid state to the solid state.
(d)
| Disease of the circulatory system | Prevention |
| High blood pressure (Hypertension) |
1. Regular exercise
|
| Low blood pressure (Hypotension) |
1. Regular exercise
|
| Piles/Haemorrhoids |
1. Eat a lot of fruits/vegetables
|
| Leukaemia/Blood cancer |
1. Avoid smoking
|
| Varicose vein |
1. Regular exercise
|
| Arteriosclerosis |
1. Regular physical exercise
|