5. On January 28, 1986, the space shuttle Challenger was
The ready for launch. However, 73 seconds after its take-
Challenger off, the shuttle met with a disaster. It disintegrated and
was completely destroyed. All seven crew members
were killed.
What happened?
How could this have been avoided?
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7. Concept Cartoons
Study the ‘problem’ situations carefully. In each case,
reasons were given by different persons. Read them
carefully and state, giving your reasons, whether you
agree or disagree with any of them. You may want to
label the persons eg. person A, B or C, on the diagram
when referring to them.
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8. Situation A
What do you think?
……………………………………………………………………………
……………………………………………………………………………
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9. Situation B
What do you think?
…………………………………………………………………………………
…………………………………………………………………………………
…………………………………………………………………………………
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10. Situation C
What do you think?
……………………………
……………………………
……………………………
……………………………
……………………………
……………………………
……………………………
……………………………
……………………………
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12. Transmission of Heat
• Heat is a form of energy
• Heat moves from an area of high
temperature to an area of low temperature
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13. Transmission of Heat
3 Methods of Heat Transfer
conduction in solids, liquids & gases
convection in liquids or gases
radiation (no medium required)
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15. Quiz
Q1
The Earth loses heat mainly by
A conduction.
B convection.
C radiation.
D all of the above.
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16. Quiz
Q2
If you are caught in freezing weather with only a candle for heat,
you would be warmest in
A an igloo.
B a wooden house.
C a car.
D a tent.
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17. Quiz
Q3
Light-coloured clothes help you cool in warm weather because
they
A weigh less.
B have a lot of spaces in them.
C reflect a lot of energy.
D absorb energy, leaving little to pass through.
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