1. Last lesson
Investigating my
(Robert Hooke)
law.

2. Forces and springs

3. Robert Hooke

4. Investigating forces and springs
You are going to investigate how much a spring stretches when a force is
applied to it.
The amount a spring stretches is called its extension. This is the
difference in length between the stretched spring and the length of the
spring when it was unstretched.
(Remember we are looking at the force on the spring. A mass of 100g will
have a weight (force of gravity pulling it down) of 1 Newton.
• Add masses to your spring and carefully measure its extension. You can do
this until the spring breaks! (but you must wear goggles and be careful
during this investigation).
Your experimental report will include the following
• A table of results
• A graph of your results
• A conclusion describing what you have discovered (think about this!)

5. Table of results
Force (N) Length of spring Extension (cm)
(cm)
0 3.4 0
1 5.4 2
2 7.4 4
3 9.4 6

6. Table of results
Force (N) Length of spring Extension (cm)
(cm)
0 0
1
2
3

7. Graph
Extension (cm)
Force (N)

8. Go!

9. Hooke’s law
Elastic limit
The extension of a
Force spring is proportional
(N) to the force applied
(until the elastic limit
is reached)
Extension (cm)

10. Can you reads pages 60
and 61 and answer the
questions on those
pages?

11. Friday 14th
November
End of Topic test
(ALL of the stuff
we’ve done this
year!)