Good Science Victorian Curriculum Year 7

INVESTIGATIONS
Investigation 6.5
Making a simple telescope
KEY SKILL
WRITING A RESEARCH QUESTION
Turn the aim of this investigation into a question that
asks what you are trying to discover. This is called a
research question.
Hint #1: Make sure that your research question has
a question mark at the end.
Hint #2: Your research question can also be used as
a title for an experiment report.
AIM
To investigate how telescopes use lenses to magnify
distant objects
MATERIALS
• metre rule
• Blu-Tack or plasticine
• retort stand
• strong convex lens (+14D) or magnifying glass
• weak convex lens (+2.5D) or lens from reading glasses
• greaseproof paper
• lamp
METHOD
1 Attach the weak lens to one end of the metre rule
with plasticine or Blu-Tack.
2 Set the metre rule into the retort stand to hold it
steady, with the weak lens pointing away from you.
3 Put the lamp on a table at the other end of the room
and turn it on.
30 min
4 Turn the retort stand until the metre rule is aimed
at the lamp.
5 Hold a piece of greaseproof paper just above the
metre rule. Move it along the rule until you see a
small image of the lamp on the paper. Have a partner
hold it at that position.
6 Hold the strong lens at the other end of the metre
rule. Using one eye, look through the lens at the
image on the paper. Move the lens until the lamp
image is magnified.
7 Have your partner take the paper away, but continue
looking through the strong lens. You should still see
the image of the lamp, although brighter than before.
QUESTIONS
1 Why does this telescope require two lenses, rather
than just one?
2 Why is the image brighter once the paper is taken
away?
3 How is this simple telescope different to a proper
telescope?
CONCLUSION
Copy and complete:
‘The results show that: (respond to the aim)’.
Level 2
168 GOOD SCIENCE VICTORIAN CURRICULUM 7