Diving

Diving

Pencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Further Resources
This task is about understanding information from a text.
illustration: bathyscope
 
Why can't you feel the weight of the air? There are several kilometres of it pressing down on you from above. Because the force of the air around you pressing in is the same as the force of the air inside you pressing out, you feel nothing. But water weighs much more than air.
 
Try holding a litre milk bottle of air in one hand and another full of water in the other. You can feel the difference. The weight of the air at ground level is called the weight of one atmosphere. Below ground level, under the surface of the sea, pressure increases – both air and water press on you. For about every ten metres you go down in the water, the pressure on your body goes up by the weight of one atmosphere.
Most sports divers don't go down much over 20 metres – dives much beyond this are not usual. This is because, by the time divers get down to 130 metres, it's as if thirteen atmospheres were pressing down on them. At 20 metres, their rib cages would be pressed in to one-third of their normal size; at 30 metres, these would be down to one-quarter of normal. At 130 metres, if the air inside their lungs was still the same kind as they were breathing at ground level, their lungs would be squashed flat. Divers going deep down must breathe a special kind of dense air – air that is compressed to the same pressure as the water round them.

Question 1Change answer

a)  How does the writer get our attention in the first paragraph?

Question

b)  If you were breathing the same kind of air you breathe at ground level, but were 30 metres below water, what would happen to your rib cage?

    • It would be pressed to one quarter of its normal size.

    • It would be pressed to one third of its normal size.

    • It would be squashed flat.

    • Nothing would happen to it.

Question 1Change answer

c)  In order to prevent injury, what pressure does the special dense air that deep sea divers breathe have to be at? 

Question 1Change answer

d) Why do most sport divers not go much deeper than 20 metres below the sea?

Question

e)  A good title for this extract would be ...

    • "All About Air Pressure"

    • "Coping With Air Pressure When Diving"

    • "The Many Dangers of Deep-Sea Diving"

    • "Why We Need Aqualungs"

Task administration: 
This task can be completed with pencil and paper or online with some auto-marking.
Copyright: 
Source: Elizabeth Ann McGilvray, 'Diving for Gold'.
Illustration by Tim Galloway.
Applications, Learning Media, 1992.
Copyright: Crown
Level:
5
Curriculum info: 
English, Making meaning, Reading
Key Competencies: 
Using language, symbols, and texts
Keywords: 
comprehension, retrieve, inference
Description of task: 
Students read a short extract on diving and answer five comprehension questions.
Curriculum Links: 
Links to the Literacy Learning Progressions for Reading:
This resource helps to identify students’ ability to:
  • use comprehension strategies
  • infer ideas and information that are not directly stated in the text
as described in the Literacy Learning Progressions for Reading at: http://www.literacyprogressions.tki.org.nz/The-Structure-of-the-Progressions.
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Acquiring and using information and ideas in informational texts, sets 5-7
Making sense of text: processing system, sets 6-7
within the Reading Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
 

Y10 (08/2000)

a)

By beginning with a question.

easy

b)

A [It would be pressed to one quarter of its normal size.]

easy

c)

At the same pressure as the water around them.

easy

d)

Any 1 of:

  • The pressure is too great.
  •  The rib cage would be pressed to one third of its size.

moderate

e)

B ["Coping With Air Pressure When Diving".]

moderate