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1st
Semester Review - EXAMINATION October –November -2014
Curriculum: MYP
1 | P a g e
SUBJECT / PAPER: PHYSICS
DATE 7 Nov CRITERIA A, B, C, D DURATION 2 Hrs. CLASS &
SEC 8MYP
General Instructions
• Do not start the paper until instructed.
• Mention the question number on the answer scripts clearly.
• Use of calculators is allowed.
• Use Black or Blue ballpoint pen only to write your answers.
• For Diagrams/ Drawings use pencil.
• Use of unfair means in any form may lead to cancellation of current paper or all.
• Students are allowed to leave the examination hall only after the end of examination.
• At the end of the examination, fasten all your work securely together.
Criterion Achievement
level
Level descriptor
Cri
teri
on
A K
no
win
g a
nd
un
der
san
din
g
0 • The student does not reach a standard described by any of the descriptors below.
1 – 2
• The student is able to: i recall scientific knowledge
ii apply scientific knowledge and understanding to suggest solutions to problems
set in familiar situations
iii apply information to make judgments.
3 – 4
• The student is able to: i state scientific knowledge
ii apply scientific knowledge and understanding to solve problems set in familiar
situations iii apply information to make scientifically supported judgments.
5 – 6
• The student is able to: i outline scientific knowledge
ii apply scientific knowledge and understanding to solve problems set in familiar
situations and suggest solutions to problems set in unfamiliar situations
iii interpret information to make scientifically supported judgments.
7 – 8
• The student is able to: i describe scientific knowledge
ii apply scientific knowledge and understanding to solve problems set in familiar
and unfamiliar situations iii analyse information to make scientifically supported judgments.
Lev
el
ach
ieved
2 | P a g e
A.(i).1 recall scientific knowledge
1. Match the following by drawing straight lines.
Particle name Charge
1. Proton Positive
2. electron Neutral
3. neutron negative
2. Opposite charges ____________________ [attract/repel].
3. The object which gains electrons has ___________________ charge. [positive/negative]
4. Metals are described as ___________________ [conductors/insulators] because they
__________________ [allow/ do not allow] electricity to pass through them.
5. Match the following by drawing straight lines.
Circuit component Name of circuit component Symbol of circuit component
Electric bulb
Electric cell
battery
Switch in ‘ON’ position
wire
Switch in ‘OFF’ position
3 | P a g e
6. Choose the correct answer by ticking the correct choice.
(i) Which shows the correct way to use an ammeter?
A.(i).2 state scientific knowledge
7. Fill in the blanks.
(i) Ammeter measures ____________________. Its unit is ______________ and symbol of the unit is
___________.
(ii) Voltmeter measures ___________________. Its unit is ______________ and symbol of the unit is
____________.
(iii) ____________________ is a device that can show whether an object has positive or negative
charge.
8. What type of circuit is described by each of the following statements? Answer ‘series’ or ‘parallel’.
(i) All components are connected end-to-end. _____________________
(ii) The current in the circuit divides so that some flows through one component and the rest through
another component. ________________________
(iii) Two identical lamps are connected side by side so that each lights brightly.________________
(iv) The current has the same value everywhere in the circuit.___________________________
A.(i).3 outline scientific knowledge
9. What are the rules of attraction and repulsion of charges?
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4 | P a g e
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10. Two balls are hanging as shown in the figure.
(i) What would happen if both the balls acquired positive charge?
…………………………………………………………………
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(ii) What would happen if both the balls acquired negative charge?
………………………………………………………………….
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(iii) What would happen if one of the balls acquired positive charge and
the other ball acquired negative charge?
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A.(i).4 describe scientific knowledge
11. Answer the following questions based on the diagram given below, which indicate the charges
present after an electrically neutral rod and cloth were rubbed together.
(a) Describe in detail how the
polythene rod and woolen cloth
become charged when they are
rubbed together. Mention how
and why the charge transfer take
place between the rod and the
cloth.
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5 | P a g e
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(b) Describe in detail how the
acrylic rod and cotton cloth
become charged when they are
rubbed together. Mention how
and why the charge transfer take
place between the rod and the
cloth.
……………………………………………………………………………………………………………
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12. What does the current from the battery do when it meets a junction (junction is a place where two or
more wires meet) in a parallel circuit?
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6 | P a g e
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13. Explain why it is better to wire house lights in parallel.
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A.(ii).1 apply scientific knowledge and understanding to suggest solutions to/solve problems set in
familiar situations
14. Choose the correct answer by ticking the correct choice.
(i) If you increase the voltage of the battery, how will the light bulb change?
A. It will look brighter because the yellow lines are brighter and longer
B. It will be less bright because the yellow lines are less bright and
shorter
C. There is no change because the bulb just uses the extra energy
without changing brightness.
7 | P a g e
(ii) If you build circuit A and then add a resistor as in circuit B, the light will
A. look brighter
B. look less bright
C. there will be no change in brightness
(iii) Answer the following questions based on the circuit diagram given below:
(a) Which resistor will have the greatest current?
A. the 50 Ω resistor
B. the 10 Ω resistor
C. both resistors have the same current
(b) Which resistor will have the greatest voltage?
A. the 50 Ω resistor
B. the 10 Ω resistor
C. both resistors have the same voltage
(iv) Answer the following questions based on the circuit diagram given below:
(a) Which resistor will have the greatest current?
A. the top resistor
B. the bottom resistor
C. both resistors have the same current
(b) Which resistor will have the greatest voltage?
A. the top resistor
B. the bottom resistor
C. both resistors have the same voltage
(v) Answer the following questions based on the circuit diagram given below:
(a) Which resistor will have the greatest current?
A. the 50 Ω resistor
B. the 10 Ω resistor
C. both resistors have the same current
(b) Which resistor will have the greatest voltage?
A. the 50 Ω resistor
B. the 10 Ω resistor
C.both resistors have the same voltage
8 | P a g e
(vi) Answer the following questions based on the circuit diagram given below:
(a) Which resistor will have the greatest current?
A. the top resistor
B. the bottom resistor
C. both resistors have the same current
(b) Which resistor will have the greatest voltage?
A. the top resistor
B. the bottom resistor
C. both resistors have the same voltage
(vii) Choose the correct options based on the diagram given below. More than one option could be
correct. So select ALL correct options.
What will happen if the voltage of the cell is increased to 20 V?
A. the voltage across the resistor will increase
B. the voltage across the resistor will decrease
C. the voltage across the resistor does not change
D. the current through the resistor will increase
E. the current through the resistor will decrease
F. the current through the resistor does not change
(viii) What is the total resistance in the following circuits?
(a)
A. 6.4 Ω
B. 21 Ω
C. 38 Ω
D. 75 Ω
9 | P a g e
(b)
A. 6.4 Ω
B. 21 Ω
C. 38 Ω
D. 75 Ω
A.(ii).1 apply scientific knowledge and understanding to suggest solutions to / solve problems set
in unfamiliar situations
15. Dimmer switches change the brightness of lights. A variable resistance is used to change the
resistance in a circuit. Variable resistors often have a control knob to change the value of the resistance.
Volume controls are made from variable resistors.
A dimmer switch uses a variable resistor. Thus, by turning the dimmer switch, you change the
resistance. When you turn the dimmer switch clockwise, it decreases the resistance. When you turn the
dimmer switch anticlockwise, it increases the resistance. You can observe this in the diagram below.
(a) Explain what happens (and why) to the brightness of the light bulb when you turn the dimmer switch
clockwise.
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10 | P a g e
…………………………………………………………………………………………………………..
(b) Explain what happens (and why) to the brightness of the light bulb when you turn the dimmer switch
anticlockwise.
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(c) Explain what happens (and why) to the brightness of the light bulbs when you add more bulbs in
series to the circuit.
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(d) Explain what happens (and why) to the brightness of the light bulbs when you add more bulbs in
parallel to the circuit.
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11 | P a g e
…………………………………………………………………………………………………………..
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16. The flow of electric current around a circuit is like the flow of water around a system of pipes. The
cell or battery is like the pump. An ammeter in the electrical circuit is like a paddle wheel that turns and
tells you how fast the water flows in the pipes. An ammeter measures the flow of electric current in
amperes. Look at the diagram below which compares an electric circuit to a water circuit and fill in the
blanks in the following tables.
electric circuit water circuit
component of electric
circuit
job component of water
circuit
job
……………………..
pushes the current
around the circuit
……………………..
pushes the water
through the pipes
charge flows around the circuit
……………………..
flows around the pipes
ammeter shows higher value if
more charge crosses it
every second
……………………..
rotates faster if more
water passes through it
every second
……………………..
can break the circuit
and stop the flow of
current
……………………..
can stop the flow of
water
12 | P a g e
A.(iii).1 apply information to make scientifically supported judgements
17. Electricity will flow ONLY when a circuit is complete. The following four diagrams show four
attempts at making a light bulb light up. Explain WHY each attempt will WORK or NOT WORK.
(a)
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(b)
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13 | P a g e
(c)
note: the circuit is connected using wooden sticks
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(d)
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14 | P a g e
A.(iii).2 interpret information to make scientifically supported judgements
18.
15 | P a g e
(b)
A.(iii).3 analyse information to make scientifically supported judgements
19. Read this information taken from a recent newspaper article.
• Researchers have found that children living close to overhead power cables are more likely to
develop leukaemia (blood cancer).
• The researchers studied two groups of children. One group had developed leukaemia, the other
group was healthy.
• Although the researchers found a link, they are unable to explain why some children got
leukaemia. They say that the results may have happened by chance.
• Other factors that have not been investigated, such as the environment, the geographical area or
the children’s genes, could be important.
• A cancer research charity said that childhood leukaemia was most likely to be caused by factors
that parents were unable to control.
(a) Why did researchers study a group of healthy children?
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16 | P a g e
(b) The information does not say how many children were studied. Why should this data have been
included in the article?
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(c) The researchers could not be certain that the overhead power cables were responsible for the
increased chance of children developing leukaemia. Explain why.
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(d) The results of the research carried out by scientists may worry some people.
What do you think scientists should do?
Put a () in the box next to your choice.
Scientists should (i) publish their research findings straight away.
(ii) not publish their research findings until they have found out as many facts as possible. Give a reason for your choice.
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17 | P a g e
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Criterion Achievement
level
Level descriptor
Cri
teri
on
B I
nq
uir
ing
an
d D
esig
nin
g
0 • The student does not reach a standard described by any of the descriptors below.
1 – 2
• The student is able to: i state a problem or question to be tested by a scientific investigation, with limited
success ii state a testable hypothesis
iii state the variables iv design a method, with limited success.
3 – 4
• The student is able to:
i state a problem or question to be tested by a scientific investigation
ii outline a testable hypothesis using scientific reasoning iii outline how to manipulate the variables, and state how relevant data will be
collected iv design a safe method in which he or she selects materials and equipment.
5 – 6
• The student is able to:
i outline a problem or question to be tested by a scientific investigation
ii outline and explain a testable hypothesis using scientific reasoning iii outline how to manipulate the variables, and outline how sufficient, relevant
data will be collected iv design a complete and safe method in which he or she selects appropriate
materials and equipment.
7 – 8
• The student is able to:
i describe a problem or question to be tested by a scientific investigation ii outline and explain a testable hypothesis using correct scientific reasoning
iii describe how to manipulate the variables, and describe how sufficient, relevant data will be collected
iv design a logical, complete and safe method in which he or she selects appropriate materials and equipment.
Lev
el A
chie
ved
18 | P a g e
B.(i) state/outline/describe a problem or question to be tested by a scientific investigation
20. You are given an ammeter to measure current, a voltmeter to measure potential difference, a cell
whose voltage can be varied, a resistance box whose resistance can be set to any value, connecting wires,
and a key.
Frame a research question of the form “How does Y depend on X?” Where Y and X are any of the
parameters like current, resistance and potential difference across the resistance.
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……………………………………………………………………………………………………………
B.(ii) state/outline/explain a testable hypothesis using scientific reasoning
21. For the above research question which you created, explain a testable hypothesis with scientific
reasoning. How do you expect whatever you chose as ‘Y’ to vary with whatever you chose as ‘X’? How will
you test it by doing an experiment?
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19 | P a g e
B.(iii).1 state the variables
22. For the above research question,
(a) what will be your independent variable?
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(b) what will be your dependent variable?
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(c) what will be your control variables?
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20 | P a g e
B.(iii).2 outline/describe how to manipulate the variables and state/outline/describe how sufficient,
relevant data will be collected
23. For the above research question, fill the blanks in the column headings and write suitable values for the
second column (independent variable).
S. No
[Independent variable name], [variable
symbol] / [symbol of unit of variable]
[………………………………………..],[………….] /
[………………]
[dependent variable name], [variable symbol] /
[symbol of unit of variable]
[………………………………………..],[………….] /
[………………]
trial 1 trial 2 trial 3 mean
1
2
3
4
5
6
7
8
9
10
B.(iv) design a logical, complete and safe method in which he or she selects appropriate materials and
equipment
24. Describe how you will conduct the experiment to take the measurements to collect the data for the
dependent variable to fill the above observation table.
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21 | P a g e
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22 | P a g e
Criterion Achievement
level
Level descriptor C
rite
rio
n C
Pro
cess
ing
an
d E
va
lua
tin
g
0 • The student does not reach a standard described by any of the descriptors below.
1 – 2
• The student is able to: i collect and present data in numerical and/or visual forms ii accurately interpret data iii state the validity of a hypothesis with limited reference to a scientific investigation iv state the validity of the method with limited reference to a scientific investigation v state limited improvements or extensions to the method.
3 – 4
• The student is able to:
i correctly collect and present data in numerical and/or visual forms ii accurately interpret data and describe results iii state the validity of a hypothesis based on the outcome of a scientific investigation iv state the validity of the method based on the outcome of a scientific investigation v state improvements or extensions to the method that would benefit the scientific
investigation.
5 – 6
• The student is able to:
i correctly collect, organize and present data in numerical and/or visual forms
ii accurately interpret data and describe results using scientific reasoning iii outline the validity of a hypothesis based on the outcome of a scientific investigation
iv outline the validity of the method based on the outcome of a scientific investigation v outline improvements or extensions to the method that would benefit the scientific
investigation.
7 – 8
• The student is able to:
i correctly collect, organize, transform and present data in numerical and/or visual forms
ii accurately interpret data and describe results using correct scientific reasoning
iii discuss the validity of a hypothesis based on the outcome of a scientific investigation iv discuss the validity of the method based on the outcome of a scientific investigation v describe improvements or extensions to the method that would benefit the scientific
investigation.
Lev
el A
chie
ved
C.(i) correctly collect, organize, transform and present data in numerical and/or visual forms
25. The following table gives the raw data collected after measuring the current through a given resistor
for different values of potential difference across it.
S.No potential difference across the resistor, V / V current, I / A
1 0 0.00
2 1 0.25
3 2 0.50
4 3 0.75
5 4 1.00
6 5 1.25
7 6 1.50
8 7 1.75
9 8 2.00
10 9 2.25
Plot the graph of current (on vertical axis) vs potential difference (on horizontal axis) in the graph below.
Remember to label the axes of the graph with variable name, unit and
cover as much area of the graph as possible.
Draw a best-fit straight line through the data points.
C.(ii) accurately interpret data and describe results using correct scientific reasoning
26. What is the slope of the above graph? Show your calculations and write the units of the slope.
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23 | P a g e
Plot the graph of current (on vertical axis) vs potential difference (on horizontal axis) in the graph below.
Remember to label the axes of the graph with variable name, unit and symbol. The data points should
cover as much area of the graph as possible.
fit straight line through the data points.
C.(ii) accurately interpret data and describe results using correct scientific reasoning
ve graph? Show your calculations and write the units of the slope.
………………………………………………………………………………………………………….
………………………………………………………………………………………………………….
………………………………………………………………………………………………………….
………………………………………………………………………………………………………….
Plot the graph of current (on vertical axis) vs potential difference (on horizontal axis) in the graph below.
symbol. The data points should
C.(ii) accurately interpret data and describe results using correct scientific reasoning
ve graph? Show your calculations and write the units of the slope.
………………………………………………………………………………………………………….
………………………………………………………………………………………………………….
………………………………………………………………………………………………………….
………………………………………………………………………………………………………….
24 | P a g e
C.(iii) state/outline/discuss the validity of a hypothesis based on the outcome of a scientific
investigation
27. Does the calculated value of the slope, support the hypothesis that the unknown resistance must be
0.25 Ω?
…………………………………………………………………………………………………………
28. Does the graph support the hypothesis that the unknown resistance is constant and does not depend
on the potential difference applied across it?
…………………………………………………………………………………………………………….
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29. To what extent is the hypothesis correct? Explain which part of the hypothesis may be right or
wrong.
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C.(iv) state/outline/discuss the validity of a method based on the outcome of a scientific
investigation
30. The above experiment was performed using the Phet simulation. Is it practically possible to change
the potential difference provided by a cell, as was done in the phet simulation?
……………………………………………………………………………………………………………
C.(v) state/outline/describe improvements or extensions to the method that would benefit the
scientific investigation
31. Suggest how you can change the potential difference across the resistance without changing the cell.
What modification do you have to make to the circuit? Draw the circuit diagram in the space below.
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25 | P a g e
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Criterion Achievement
level
Level descriptor
Cri
teri
on
D R
efle
ctin
g o
n t
he
imp
act
s o
f S
cien
ce
0 • The student does not reach a standard described by any of the descriptors below.
1 – 2
• The student is able to:
i state the ways in which science is used to address a specific problem or issue ii state the implications of the use of science to solve a specific problem or issue,
interacting with a factor
iii apply scientific language to communicate understanding but does so with limited success
iv document sources, with limited success.
3 – 4
• The student is able to:
i outline the ways in which science is used to address a specific problem or issue ii outline the implications of using science to solve a specific problem or issue,
interacting with a factor iii sometimes apply understanding scientific language to communicate
iv sometimes document sources correctly.
5 – 6
• The student is able to:
i summarize the ways in which science is applied and used to address a specific problem or issue
ii describe the implications of using science and its application to solve a specific problem or issue, interacting with a factor
iii usually apply scientific language to communicate understanding clearly and precisely
iv usually document sources correctly.
7 – 8
• The student is able to:
i describe the ways in which science is applied and used to address a specific problem or issue
ii discuss and analyse the implications of using science and its application to solve a specific problem or issue, interacting with a factor
iii consistently apply scientific language to communicate understanding clearly and precisely
iv document sources completely.
Lev
el A
chie
ved
26 | P a g e
D.(i) state/outline/summarize/describe the ways in which science is applied and used to address a specific
problem or issue
32. Power stations produce electricity in large quantities to meet the requirements of the population in a city. But
the power stations also produce a lot of pollution and are a hazard for the population. So power stations are usually
set up very far away from the residential areas for safety purposes. This creates the problem of transporting the
electrical energy to the people living in the cities who need to use it. Describe the ways in which science is applied to
solve this problem. Use the picture clue given below.
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33. Before the discovery of the light bulb, people used to depend on burning of fuel to produce light. This used to
produce less light and caused pollution. After the discovery of electricity, many researchers tried to produce light by
passing electricity through different materials so that they became red hot or white hot and emitted light by
glowing. But they faced the problem that the materials soon caught fire and burned completely, almost immediately
after they started glowing and emitting light. How did Edison apply science to solve this problem? Explain in detail.
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34. Since the fluorescent tubes and the incandescent light bulbs consume lot of electricity to produce the bright
light, researchers have been trying to find a more efficient source of light energy. This year’s Nobel Prize in physics
was awarded to the following three people:
for the invention of efficient ……………………………………………………………………………………………. which has enabled bright
and energy-saving white light sources.
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D.(ii) state/outline/describe/discuss and analyse the implications of using science and its application to solve a
specific problem or issue, interacting with a factor.
35. People need electricity to power all their electrical devices. So electricity needs to be supplied to homes at high
voltages (around 220 V) to meet the electricity requirements. Science has solved this problem by the use of high
voltage transmission with the help of transformers and electric cables. But high voltage electricity is dangerous since
it can cause fire. Read the following news clipping from the Times of India to get an idea about the dangers of using
electricity without adequate safety measures.
Mumbai has most short-circuit fires and deaths in India
Mumbai is the most dangerous city in the country as far as fires caused by short-circuit go. From 2009 to 2013, 285 short-circuit-caused fires occurred in Maharashtra's capital city, compared to 196 in Delhi, which is second on a list released by the National Crime Records Bureau (NCRB) a little over a month ago. The incidents, brought into focus because of Friday's Vashi hotel and Thane coaching class fires, were reported from commercial and residential buildings. Experts say short-circuits usually occur because people use poor equipment or do not maintain them.
Fire brigade and police officers say short-circuit is mainly caused by the use of electrical equipment
of poor quality. They say that despite safe-practice campaigns on TV and in newspapers, most people
ignore instructions. "Most short-circuit-caused fires begin in air-conditioners or power mains. Even
if people buy quality equipment, they don't maintain them, leading to deterioration in the quality of
wire coverings. Overloading of lines is another cause," said a fire officer.
"Poor maintenance leads to erosion of the coatings of wires, making them exposed. A short-circuit is
caused when such wires carrying electricity come in contact," said Mumbai's deputy chief fire officer
P S Rahangdale.
Another reason is littering of ducts and dumping waste in areas close to electrical equipment or
wires. "Waste paper and such matter easily catch and spread fire. Again, many buildings don't have
garbage corners, encouraging people to litter," said the officials.
As for casualties, "the majority of deaths is caused due to panicking and suffocation", said
Rahangdale.
As for prevention, experts suggest various precautions, including not allowing AC ducting to pass
through floors. "Fire, heat and smoke travel through ducts and spread to other parts of a building.
So, it is important to sectionalize them," said an expert. "This should be done, as far as practical, even
on individual floors to limit the spread of fire, heat and smoke, minimising damage."
Based on the above news clipping, answer the following questions regarding the problem of how to use
electricity safely and prevent any accidents caused by electricity.
(a) Explain what happens if we use electricity without understanding it, and without following any safety
measures. Give examples.
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(b) Which is the most dangerous city in India because of fires caused by short-circuits? Support your
answer with facts.
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(c) Where do most short-circuit fires begin?
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(d) What are the two main causes of short-circuit fires?
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(e) Why is it dangerous to litter near ducts and areas close to electrical equipment and wires?
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(f) What is the major cause of death in fires caused by short-circuits?
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(g) What precaution can be taken while constructing houses to limit the spread of fire, heat and smoke in
the event of a fire caused by short-circuit?
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