Science - Sure Shot Topics + Most Important Questions Class 10 .pdf

Short question practice

1. SCIENCE
Sure Shot Topics + Questions
#sciencesamaapt
TARGET 80/80

2. Before videoAfter Video

3. Science
Sure Shot Topics + Questions

4. Chemical Reactions & Equations

6. (Exothermic Reaction)

7. Q. A solution of a substance X is used for white washing.
Name the substance X and write its formula. Write the
reaction of the substance X named in above with water.

8. Displacement Reaction

9. Q.

10. Double Displacement Reaction

11. Black & White Photography
(Thermal Decomposition Reaction)

12. Oxidation Reduction Reaction

13. Rusting & Corrosion

14. Activity Bases Questions

15. Acids, Bases & Salts

17. Q. Why should curd and sour substances not be
kept in brass and copper vessels?
Reason : Metals + Acids = Salt + H2
This can be poisonous for us.
Q. Metal compound A reacts with dilute Hydrochloric acid to produce
effervescence. The gas evolved extinguishes a burning candle. Write a
balanced chemical equation for the reaction if one of the compounds
formed is Calcium chloride.

18. Indicators
Q. Meena rubbed the yellow-colored
turmeric stain on his son’s shirt with
soap. She observed the color of the
stain became:
a. Pink
b. Reddish brown
c. Remained yellow
d. White

19. Important reactions for questions

20. Properties of Acids
& Bases
Q. Why does aqueous solution of an
acids conduct electricity

21. Metal Carbonate Reaction with Acids
CO2 gas test - Turns Lime water milky

22. H2 & CO2 gas testing
CO2 gas test - Turns Lime water milky
H2 gas test - Burns with a pop sound

23. Chlor - Alkali Process

24. Baking Soda & Baking Powder
Q. Which gas causes the bread or
cake to rise making them soft and
spongy?

25. POP & Gypsum
Q. A white powder is used by doctors
to support fractured bones.
(a)Write the name and chemical
formula of the powder.
(b)How is this powder prepared?
(c)When this white powder is mixed
with water, a hard solid mass is
obtained. Write a balanced
chemical equation for the change.

26. Bleaching Powder
Q. A yellow powder X gives a
pungent smell if left open in air. It is
prepared by the reaction of dry
compound Y with chlorine gas. It is
used for disinfecting drinking water.
Identify X and Y and write the
reaction involved.

27. Washing SODA

28. pH - VERY IMPORTANT
pH in daily LIFE
Questions like bee sting, ant
sting (contain methanoic acid,
pH 5-5.5)

29. Metals & Non-Metals

31. When the metal carbonates
and hydrogen carbonates
react with the acids, they
produce salt and water and
liberate the carbon dioxide
gas. Metal carbonate + Acid
Salt + carbon dioxide +
water. Metal Hydrogen
carbonate + Acid Salt +
carbon dioxide + water.

32. Q. Why Hydrogen gas is not
released when metal reacts
with Nitric Acid
Compare in tabular form the
reactivities of the following metals
with cold and hot water:
(2020)
(a) Sodium
(b) Calcium
(c) Magnesium

33. Metals & Non-Metals Reaction
Q an element with atomic
number_____ will form a basic
oxide
a) 7 (2,5)
b) 17 (2,8,7)
c) 14 (2,8,4)
d) 11 (2,8,1)

34. Metals & Non-Metals Reaction

35. Roasting & Calcination

36. Roasting & Calcination

37. A thermite reaction is basically iron oxide (rust) reacting with
aluminum to produce molten iron. The products are aluminium
oxide, elemental iron, and a large amount of heat. The reactants
are commonly or thermite mixture is aluminum powder and iron
oxide (rust) powder. When the mixture is heated, it starts reacting
as the aluminum is more reactive than the iron and aluminium
forms stronger and stable bonds with oxygen than iron.
Q. What is Thermite Reaction?
Explain its use and give equation.

38. Extracting Metals towards the Top of the
Activity Series

39. Electrolytic Refining

40. Rusting, Corrosion &
Alloys
Iron, Copper & Silver Corrosion

41. Carbon & it’s Compounds

42. HYDROCARBONS
(Ethane, ethene, ethyne)

43. Reactions of Ethanol
Reaction of Ethanoic Acid

44. Esterification Reaction
Saponification Reaction
Oxidation Reaction

45. Addition Reaction

46. Substitution Reaction

47. IUPAC Nomenclature
Soaps & Detergents

48. Q. What is ethanoic acid? Write the formula of the functional group
present in this acid.
What special name is given to its 5 – 8% solution in water? How does
ethanoic acid react with sodium carbonate? Write a chemical equation
of the reaction and common name of the salt produced.

49. Q With the help of balanced chemical equations
explain what happens when ethanol is heated with (i)
alkaline solution of potassium permanganate,
(ii) excess concentrated sulphuric acid at 443 K.
Mention any two uses of ethanol.
Q. Write the molecular formula of the 2nd and 3rd
member of the homologous series whose first member
is ethene.

50. (a) State the reason why carbon can neither form C4+ cations nor C4- anions, but forms
covalent bonds. Also state reasons to explain why covalent compounds
(i) are bad conductors of electricity
(ii) have (ow melting and boiling points.
(b) Write the structural formula of benzene, C6H6. (AI2019)
Q. A compound ‘X’ on heating with excess cone, sulphuric acid at 443 K
gives an unsaturated compound ‘Y’. ‘X’ also reacts with sodium metal
to evolve a colourless gas ‘Z’. Identify ‘X’, ‘Y’ and ‘Z’. Write the equation
of the chemical reaction of formation of ‘Y’ and also write the role of
sulphuric acid in the reaction.

51. Life Processes

52. Respiration
Q. a. Why is there a difference in the rate of breathing between
aquatic and terrestrial organisms explain.
b. Draw a labelled diagram of Human Respiratory System
(2020,2017)
Q. Difference between aerobic and anaerobic respiration
Q. Respiration in presence/lack/absesnce of oxygen
what are the different ways glucose is oxidised to provide energy
Q.Respiratory pigment in Humans - Haemoglobin

53. Excretion
(a) Name the various organs of the human excretory system.
(b) Draw a neat labeled diagram of the human excretory system.
(c) What is the function of the excretory system in humans?
(2017,2018,2020,2022)

54. Transportation (Heart)
(a) Mention any two components of
blood.
(b) Trace the movement of
oxygenated blood in the body.
(c) Write the function of valves
present in between atria and
ventricles.
(d) Write one structural difference
between the composition of artery
and veins.

55. Transportation in Plants
Xylem - unidirectional
Phloem - birdirectional

56. Q. (a) Write two water conducting tissues present in plants. How
does water enter continuously into the root xylem?
(b) Explain why plants have low energy needs as compared to
animals. (2016,18,19)
(a) Xylem tracheids and xylem vessels are water-conducting tissues (vascular tissue) as part of the xylem
present in plants. Xylem is responsible for the conduction of water from the roots to other parts of the plant.
Due to transpiration and the resulting pressure gradient, water is absorbed into the root xylem of plants. The
transpirational pull formed causes the roots to absorb water from the soil and resulting in the transportation
of water.
(b) Plants have low energy needs as compared to animals due to the following reasons:
(i) Plants are autotrophic organisms, preparing their own food absorbing solar energy during the process of
photosynthesis.
(ii) Plants don't move from one place to another like animals so they consume less energy.
(iii) Also, plants possess many dead cells in terms of sclerenchyma cells that do not require much energy for
maintenance.

57. Digestion
(i) Draw a well-labeled diagram of
human digestive system (ii)Describe the
role of following in digestion
. a)Bile
b)Salivary amylase
c)HCl
Name of all the juices & their functions.
1. Draw the labeled diagram of the human
digestive • system.
2. Give reasons for the following:
(i) The glottis is guarded by epiglottis. (ti) It is
said to not speak while eating. iii) Walls of
trachea are supported by cartilage rings

58. 1-mark MIQ
Q. Why do arteries have thick & elastic walls
The heart pumps the blood with force which may cause rupture of
blood vessels that are thin walled. That is the reason arteries have
thick walls which can withstand high amounts of pressure.
Q. What is respiratory pigment in humans?
Ans - Haemoglobin
Q. Oxygenated & deoxygenated blood carriers
Q. Why is it necessary to separate oxygenated and deoxygenated
blood in mammal and birds ? Give examples.
Ans - Allows high supply of oxygen to the body

59. Q. Mention site of complete digestion of fats, proteins & carbohydrates
Q. Ventricles have thicker muscular walls than artia. Explain
Q. Questions on type of nutrition like : saprophytic, parasitic

60. Reproduction

61. 1. Reproduction & Variations (advantage)
2. Method of Asexual reproduction with examples
3. Vegetative Propagation
3. Sexual reproduction in Plants
4. Sexual reproduction in Humans
5 Reproductive Health (contraceptive
advantage and disadvantage)
Topics

62. Q. Why is DNA copying important in reproduction?
Q. Variation is beneficial to the species, but it is not
necessary for the individual.

63. Asexual Reproduction
Binary Fission - Amoeba
Multiple Fission - Plasmodium
Budding - Yeast & Hydra
Fragmentation - Spirogyra
Regeneration - Planaria
Spore Formation - Rhizopus

64. Q. What is spore formation
Draw a diagram & list 2 advantages

65. Vegetative Propagation

66. Q. Name 2 Plants grown by vegetative propagation
Ans - Sugarcane, rose, pineapple etc
Q. Vegetative propagation is practised for growing some
plants. Give a reason and explain why vegetative
propagation is important

67. Sexual Reproduction in Flowers
Q. Draw a labelled diagram of the longitudinal section of a flower.
& explain germination, pollination & how fertilisation occurs.
Q. Define Pollination & types of
pollination & agents

68. Sexual Reproduction in Humans

69. Q. Draw a diagram of the human female reproductive system
and label the part
(i) that produces eggs.
(ii) where the fusion of egg and sperm takes place.
(ili) where the zygote is implanted.
What happens to a human egg when it is not fertilised?

70. Q. Draw a diagram of the male reproductive system and label
the parts
(i) that produces sperm cells
Q. Explain the entire process of Sexual reproduction in
Humans

71. Q. Difference between sexual/asexual reproduction or
advantages of sexual over asexual reproduction

72. Reproductive Health in Humans
Q. The sexual act always has the potential to lead to pregnancy.
Pregnancy will make major demands on the body and the mind of
the woman, and if she is not ready for it, her health will be adversely
affected. Therefore, many ways have been devised to avoid
pregnancy.
1.What are the different methods to prevent pregnancy?
2. What are the surgical methods to prevent pregnancy?.
3. Why the female sex ratio is declining day by day?
4. Which contraceptive methods have large side effects?

73. Control &
Coordination

74. Q. How do control and coordination differ in plants and animals?
(humans are complex, we have nervous and hormonal system)
Q. Draw a labelled diagram of human brain and write functions
of it’s various parts

75. 03. What are plant hormones ?
Name the plant hormones responsible for the following:
(1) Growth of stem
(2) Promotion of cell division
(3) Inhibition of growth
(4) Elongation of cells

76. Q. Draw a well labelled diagram of reflex arc

77. It’s an important chapter, so try reading all
the concepts

78. Heredity and Evolution

79. (a) Wrinkled and yellow
(b) round and green
(c) wrinkled and green
(d) round and yellow.
It a round green seeded pea plant (RRYY) is crossed with
wrinkled yellow
seeded pea plant (rr yy) the seeds to be produced in 1 F
generation will be.
(Q-1)
Answer :b

80. Acquired traits are those that organisms
develop over the course of their lives. These
characteristics can't be handed down because
they're caused by non-reproductive tissue
Why acquired traits are not inherited?
(Q-2)
Answer :

81. The organisation of organisms into groups based on their properties is known
as classification. Characteristics are physical or behavioural characteristics.
The most advanced and effective classification system is based on evolution.
The division of organisms/species into groups reflects their shared origins, as
well as their evolutionary relationship
How evolution and classification are linked?
(Q-3)
Answer :

82. The term "gene" refers to DNA segments.
Chromosomes are where genes are found.
What is gene? Where are genes located?
(Q-4)
Answer :

83. Write difference between Autosomes and
Allosomes
(Q-5)
Answer :

84. Monohybrid cross- This is the simplest cross in which only one character's
inheritance is investigated. A cross is created by crossing two plants with one
contrasting characteristic, such as tall or dwarf.
Dihybrid cross- A dihybrid cross is a cross between two plants with two sets of
opposing characters. Round and green seed, for example, crossed with yellow and
wrinkled seed
What is monohybrid and dihybrid cross?
Give one example of each.
(Q-6)
Answer :

85. Mendel chose the garden pea for his experiment for the following reasons:
(a) Because this plant has a short life cycle, the results may be gathered and
evaluated more quickly.
(b) The garden pea possesses a number of features that are diametrically
opposed to
one another.
(c) This plant is also tiny, easy to grow, and produces a big number of
offspring.
Why did Mendel choose pea plant for his
experimentation?
(Q-7)
Answer :

86. Humans differ from one another in terms of size and colour, but they are all
members of the same species. This is due to the fact that, despite the tremendous
diversity of human shapes and traits among different human races around the world,
all human beings' genetic footprints can be traced back to the same common heritage
of African origins. Humans are a single species that descended from the earliest
members of the human species in Africa, Homo sapiens. Because there has been no well-
defined geographical or reproductive isolation among members of the human species,
this has resulted in a wide range of genetic makeups for features with minor differences.
Why are human beings who look so different from each
other in terms of
size, colour and looks said to belong to the same species?
(Q-8)
Answer :

87. Asexual reproduction tends to preserve the genetic similarities
among all members of a line of descent. As a result, asexually
reproducing organisms can exhibit hereditary characteristics
Why are asexually reproducing organisms
capable of showing hereditary features?
(Q-9)
Answer :

88. Offspring are organisms that are raised as
a result of gene segment crossing and
exchange in sexual reproduction.
What is an offspring?(Q-10)
Answer :

89. Homologous organs have a similar basic structure and
origin, but may perform diverse tasks. Human hands, for
example, and avian wings, for example.
Organs that have a similar function but a different basic
structure and origin are referred to as comparable organs.
For example,
(1) a bat's wing and a bird's wing.
(2) a bird's wing and an insect's wing
What are homologous and analogous
organ? Explain with the help of example.
(Q-11)
Answer :

90. Mendel’s law-
(a) Law of dominance- When two distinct character factors are
present in an organism, only one (dominant factor) manifests
itself, while the other (recessive factor) remains unexpressed.
(b) Principle of segregation –At the moment of gamete
formation, two elements of a character are separated, and each
gamete receives only one factor for that character.
(c) Principle of independent assortment-This concept asserts
that one pair of contrasting qualities is independent of the other
pair of contrasting traits when two or more pairs of contrasting
traits are inherited
State three laws of Mendel(Q-12)
Answer :

91. Males have the ability to create either X-type or Y-
type gametes. The females only generate the X-type of
gametes or ova. If X-type sperm unites with the ovum, the
infant will have a feminine sex. If Y-type sperm is used in
conjunction with the ovum, the kid will be male. The
baby's gender is determined at the time of conception.
The baby's sex is determined at the time of conception.
Describe how the sex of the offspring is
determined in the zygote in human beings?
(Q-13)
Answer :

92. Fossils are preserved evidence of living animals that are found
closer to the earth's surface and are more recent in origin than
fossils discovered in deeper layers. Fossils can also aid in the
discovery of evolutionary relationships between creatures
What are fossils? What do they tell us about
the process of evolution?
(Q-14)
Answer :

93. Geographic isolation can, in fact, lead to speciation. As a result
of genetic drift,
members of two subgroups may not be able to interbreed due
to geographical
isolation. Natural selection works differently in these subgroups
as well. Speciation
occurs as a result of this.
Can geographical isolation lead to
speciation? How?
(Q-15)
Answer :

94. Our Environment

95. (a) methane
(b) carbon-dioxide
(c) Sulphur-dioxide
(d) CFCs
Ozone layer is damaged by-
(Q-1)
Answer :d

96. Any form of precipitation that contains high levels of
nitric and sulfuric acids is called acid rain. It can also
occur in the form of snow, fog, and tiny bits of dry
material that settle to Earth.
The harmful effects of acid rain are-
It effects human nervous system, respiratory system
and digestive system.
It can also leach aluminium from the soil.
What is acid rain?
(Q-2)
Answer :

97. Only 10% of energy is available at the next trophic level in 10% law. For example-Suppose 1000 Joules
of light energy emitted by the sun falls on the plants. Then the plants or first trophic level has 10
joules of energy in it. Now according to 10 percent law, only 10% of 10 joules of energy (which is 1
joule) will be available for transfer to the next trophic level, so that the herbivore will have only 1 joule
of energy stored as food at the second trophic level. 10% of the remaining 1 joule will be transferred
to third trophic level of carnivore. So, the energy available in the lion as food will be only 0.1 joule.
What is 10% law? Give an example
(Q-3)
Answer :

98. Energy transfer is unidirectional because when the energy is absorbed by autotrophs
from the sun, it is never reabsorbed by it. And when consumers eat up the producers
directly or indirectly the energy transferred in this process can never be reversed in
the food chain. In biogeochemical transfer is cyclic because chemical elements
move from environment to organism and back to the environment.
Energy transfer is said to be unidirectional
whereas biochemical transfer is said to be
cyclic. Why?
(Q-4)
Answer :

99. How would you dispose the following wastes?
a) domestic wastes like vegetables peels
b) industrial wastes
(Q-5)
Answer :
Domestic wastes should be disposed off in a pit.
Industrial wastes should be treated first to remove
poisonous chemicals and
then disposed off in water resources.

100. Abiotic components
Abiotic factors are the non-living things of an ecosystem.
It cannot adapt as per the environmental conditions
Sunlight, temperature, water are the examples of abiotic
components.
Biotic components
Biotic factors are the living things of an ecosystem.
It can adapt to the changes in the environment
Plants, tress, animals are the examples of biotic components.
Differentiate between abiotic and biotic
components of ecosystem.
(Q-6)
Answer :

101. The two methods reducing the problem of waste
disposal are-
Practicing the 3 R's: Reduce, Reuse and
Recycle.
By throwing biodegradable and non-
biodegradable waste into separate dustbins so
that recycling can be done easily.
Give any two methods reducing the problem
of waste disposal.
(Q-7)
Answer :

102. The position that an organism occupied in a food
chain is called trophic level.
An example of a food chain and state the different
trophic level in it is as follows:
Plants (Producer) -> Deer (Primary consumer) ->
Lion (Secondary consumer)
What are trophic levels? Give an example of a food chain
and state the
different trophic level in it.
(Q-8)
Answer :

103. What is ozone and how does it affect any
ecosystem?
(Q-9)
Answer :
Ozone is a gas composed of three atoms of oxygen. Its
molecular formula is
O . It forms a layer in the upper atmosphere. It is very essential for
the life on this
planet. It shields the surface of the earth from ultra-violet radiation
(UV) coming
from sun as these radiations are very harmful causing skin cancer
and cataract in
humans. It also does harm to the crops.
3
The harmful effects of ozone depletion are-
Causes skin cancers
Causes eye cataracts
Leads to immune deficiency disorders.
Affect plant growth
Reduces agricultural productivity.

104. Gathering of various unimportant and harmful substances
by organisms at different levels of a food chain is known as
biological magnification. Its causes are the excessive use of
pesticides which enter our food chain. As The bottom
feeders of a food chain consume these and gradually it is
carried to the top of that particular food chain.
What is biological magnification and
give its causes?
(Q-10)
Answer :

105. Some substances are biodegradable and some non-biodegradable because
some substances can be decomposed by microorganisms and some cannot as he
micro-organisms like bacteria and other decomposers organisms (called
saprophytes) present in our environment specific in their action. They break down
the materials or products made from natural materials (paper) as they have some
peculiar enzymes for this process. But as enzymes are specific in their action, these
cannot break down many man-made materials likes plastic. These can be acted upon
by physical processes but not by biological processes. Therefore, these types of
substances persist for long time and cannot be decomposed into simpler substances
Why are some substances biodegradables
and some non-biodegradable?
(Q-11)
Answer :

106. Food chain- The food chain describes which organism in the environment eats
another organism. In ecology, the food chain is the series of transfer of matter and
energy from organisms to organisms in the form of food. It is the sequence of events
in an environment or ecosystem in which one living organism eats another living
organism and another larger organism eats that organism later. It is a part of food
web.
Food web- Food web means, mutually, many food chains via which energy flows
into the ecosystem. The Food web is an interconnection of the various food web. A
food web is just like the food chain except that the food web is larger than the food
chain. Rarely, one organism is eaten by multiple predators, or it consumes many
other organisms. The food webs are more complex.
What is the difference between food chain and
food web?
(Q-12)
Answer :

107. If all the carnivores are removed from the earth, the population
of herbivores
will increase. Large population of herbivores will overgraze. And
all plants will
disappear from the earth surface and ultimately the earth may
become a desert. The
biosphere will get disturbed which will lead to end of life on earth.
What will happen if all the carnivores are
removed from the earth?
(Q-13)
Answer :

108. Decomposers are the organisms which depend upon the dead and decaying
organisms their waste material. They form important link between living and nonliving
components. They are important because Decomposers decompose the
complex substances into simple ones so that plants can use it again.
What are decomposers and what is the importance of
them in the ecosystem?
(Q-14)
Answer :

109. Food chains consist of three or four steps only is
because of 10% law as only
10% of energy is available at the next trophic level.
As If a food chain has six or
more than six steps, energy is not sufficient for the
survival of organism at that
trophic level.
Why food chains consist of three or four
steps only?
(Q-15)
Answer :

111. Electricity

112. All formulas

113. Solve All Examples from NCERT

114. Q.
Q.

115. Q.
Q.

116. Q.
Q.

117. Q. Draw a schematic diagram of a circuit consisting of a battery of
three cells of 2 V each, a 5 Ω
resistor, an 8Ω resistor and a 12Ω
resistor and a plug key, all connected in series.
Q. An electric kettle of 2kw is used for 2h . Calculate the energy consumed
in
1.) Kilowatt hour
2.) Joules

118. LIGHT

119. All formulas

120. Image formation by Mirrors and
lenses

122. Q.

123. Q.
Q.

124. Q.

125. Human Eye & The
Colourful

126. Human eye : It’s
parts & functions

127. Human eye defects
Correction - concave
short sightedness
Correction - convex
far sightedness

128. Correction - concave
short sightedness
Correction - convex
far sightedness

130. Dispersion of white light by prism

131. Rainbow formation
Twinkling of stars
Tyndall Effect
Sky appears blue
Early sunrise and sunset

132. Magnetic Effects of
Electric Current

134. Domestic Circuit
Q. Explain Domestic Circuit
Q. Function of Earth wire and fuse in
domestic circuit
Q. Importance of earth wire

135. Q. Function of Earth wire and fuse in
domestic circuit
Q. Importance of earth wire

136. (a) Mechanical energy into electrical energy
(b) Mechanical energy into heat energy
(c) Electrical energy into heat energy
(d) Electrical energy into mechanical energy
(Q-1) Electric motor converts
Answer :(d)

137. The two properties of magnetic lines of force are:
i. The strength of the magnetic field is proportional to the closeness
of the lines.
ii. They can never cross i.e. the field is unique at any point in space.
(Q-2) State two properties of magnetic lines of force?
Answer :

138. If two magnetic field lines intersect each
other then there will be two
directions of magnetic field, which is not
possible. Thus, they do not intersect
each other.
(Q-3) Why do not two magnetic field lines intersect
each other?
Answer :

139. Right hand thumb rule is used to determine the direction of magnetic field
produced around a straight conductor carrying current. It states that if we hold the
current-carrying conductor in our right hand such that the thumb points the
direction of the current, then the direction in which the fingers encircle, gives the
direction of magnetic lines
(Q-4) Name and state rule used to determine the direction of magnetic
field produced around a straight conductor carrying current?
Answer :

140. Answer :
Electric fuse is a safety device which is used to
limit the current in an electric
circuit which is made up of a wire made of copper
or aluminium or a tin lead
alloy. It is always connected in series at the
beginning of the circuit.
(Q-5) What is electric fuse? Where is it connected in a circuit?

141. Answer :
They are the type of magnet in which the magnetic field is produced by an
electric current i.e. when current is passed through a solenoid it behaves as a
magnet and is called an electromagnet.
The two uses of an electromagnet are
i. Used in electrical devices like motors, generators etc.
ii. Used to lift heavy iron pieces.
(Q-6) What is an electromagnet? Write two uses of an
electromagnet?The colour that is scattered the least by the
tiny particles and the atoms/ molecules of the atmosphere is?

142. Answer :
An electric short circuit occurs when the current in the circuit rises rapidly
and the electrical connection draws an excessive amount of current from the
supply it is because if either the insulation of wires used in an electric circuit is
damaged or there is a fault in the appliances, live wire and neutral wire may
come
in direct contact.
(Q-7) When does an electric short circuit occur?

143. Answer :
The earth wire is used for the safety measures that have green insulation and
is connected to a metal plate deep in the earth near our houses. Appliances like
the electric press, toaster, table fan, refrigerator, etc have the metallic body that
needs to connect to the earth wire this will provide a low resistance path for the.
Thus, if any leakage of current occurs to the metallic body of the appliance it
keeps potential to that of the earth, and this may prevent the severe electric shock
(Q-8) What is the function of an earth wire? Why is it necessary to
earth metallic casing of electric appliances?

144. Answer :
Electric motor is a rotating device that can convert electrical energy into
mechanical energy. Which works on the principle that a current-carrying
conductor placed perpendicular to a magnetic field experience a force.
(Q-9) What is the principle of electric motor?

145. Answer :
A solenoid is a coil that has many circular turns of insulated copper wire,
which are arranged closely in the shape of a cylinder.
(Q-10) What is a solenoid? Draw magnetic field lines
showing the magnetic field
inside and outside the current-carrying solenoid?

146. Answer :
Overloading means a huge amount of current flows in the circuit. It can
occur when live and neutral wires come into direct contact. It can be avoided by
not using too many appliances in a single socket and by using a fuse in the circuit
which can prevent damage to the appliances and the circuit.(Q-11) What is overloading? How can you avoid overloading?

147. Answer :
The compass needle is a small bar magnet. When a compass needle is
brought near a bar magnet, its magnetic field lines interact with that of the
compass needle. Then due to repulsive force between like poles and attraction
between unlike poles, the compass needle is deflected.
(Q-12) Why does a compass needle get deflected when brought
near a bar magnet?

148. Answer :
If a coil is moved rapidly between the south and north poles of a horseshoe
magnet, relative to a coil the magnet is moved, and By keeping the coil still and
rotating a magnet inside it are the different ways to induce a current in a coil.
(Q-13) Explain different ways to induce current in a coil.

149. Answer :
Fleming’s left-hand rule states that stretch the forefinger, the central finger,
and the thumb of your left hand in a way they mutually perpendicular to each
other. If the forefinger shows the direction of the magnetic field and the central
finger that of the current, then the thumb will point towards the direction of
motion of the conductor or the force acting.
(Q-14) State Fleming’s left-hand rule.

150. Answer :
(Q-15) Distinguish between A.C and D.C?