P2 Radiation and life- Questions
P2.1 What types of electromagnetic radiation are there? What
happens when radiation hits an object?
1. Describe how one object affects another some distance away in terms of a general model of
electromagnetic radiation. Use the terms: radiate, reflect, transmit and absorbed.
2. True or false: light is one of a family of radiations called the electromagnetic spectrum?
3. What are the ‘packets’ of energy that transfer electromagnetic radiation called?
4. How does the frequency of the electromagnetic radiation affect the energy transferred by each
photon?
5. List the electromagnetic radiations in order of the energy transferred by each photon.
6. List the electromagnetic radiations in order of frequency.
7. Visible light travels at 300 000 km/s through a vacuum, but what speed do:
a) Gamma rays travel at?
b) Radio waves travel at?
8. What is the intensity of a beam of electromagnetic radiation?
9. The energy transferred to an absorber by a beam of electromagnetic radiation depends on what
two factors?
10. Explain why the intensity of a beam of electromagnetic radiation decreases with distance from
the source.
11. Which parts of the electromagnetic spectrum have enough energy to change atoms or
molecules?
12. Which parts of the electromagnetic spectrum can cause ionisation and why?
P2.2 Which types of electromagnetic radiation harm living tissue and
why?
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
What affect does the heating effect of absorbed radiation have on living cells?
Are there any health risks from low intensity microwave radiation?
What sort of radiation do mobile phone handsets and masts emit?
What substances can microwaves be used to heat?
Why do microwave ovens have metal cases and door screens?
True or false: some materials emit ionising gamma radiation all the time?
What are the long term effects of exposure to ionising radiation?
What does the ozone layer do?
What are the beneficial effects of the ozone layer for living organisms?
How can we protect ourselves from the harmful effects of the Sun?
How can we stop ionising radiation?
P2.3 What is the evidence for global warming, why might it be
occurring, and how serious a threat is it?
1. At what frequency do all objects emit electromagnetic radiation?
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P2- Radiation and Life
Questions
2. Does the atmosphere allow electromagnetic radiation from the Sun to pass through it?
3. Know that this radiation warms the Earth’s surface when it is absorbed?
4. Know and understand that the radiation emitted by the Earth, which has a lower principal
frequency than that emitted by the Sun, is absorbed or reflected back by some gases in the
atmosphere; this keeps the Earth warmer than it would otherwise be and is called the
greenhouse effect.
5. What are the three of the main green house gases?
6. Use the carbon cycle to explain:
a. why, for thousands of years, the amount of carbon dioxide in the Earth’s atmosphere
was approximately constant
b. why, during the past two hundred years, the amount of carbon dioxide in the
atmosphere has been steadily rising
7. Do organisms remove or return carbon dioxide to the atmosphere?
8. What are the two main reasons for the increase in atmospheric carbon dioxide?
9. HT only: What evidence is there that human activities are causing global warming?
10. What are three possible results of global warming?
P2.4 How are electromagnetic waves used in communications?
1. Give two reasons why electromagnetic radiation of some frequencies can be used for
transmitting information.
2. What is the name of the wave that the information is added to create a signal?
3. How can the signal vary in an analogue signal?
4. How can the signal vary in a digital signal?
5. True or False: sound and images can be transmitted digitally?
6. In digital transmission, the digital code is made up from how many symbols? What are these
symbols?
7. How are the symbols used in digital transmission represented by electromagnetic carrier waves?
8. What is are two important advantages of digital signals over analogue signals?
9. What is the amount of information needed to store an image or sound measured in?
10. How is the amount of information stored related to the quality of the image or sound?
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