HOOKE'S LAW
2 marks · EasyDescribe what is meant by the ‘elastic limit’ of a spring and what happens to the spring if it is stretched beyond this point.
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The elastic limit is the maximum extension (or force) a spring can experience and still return to its original shape. If a spring is stretched beyond this point, it will not return to its original length and will be permanently deformed.
Also accept: It stays stretched and does not return to its shape; it is permanently deformed after passing the elastic limit.
Common mistakes: Saying the spring instantly breaks beyond elastic limit (breaking may happen later).
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Marking points
B1 · 1 mark · Defines elastic limit as the point at which a spring stops returning to original shape after stretching.
B2 · 1 mark · States that beyond the elastic limit, the spring is permanently deformed/does not return to original length.
Worked solution
The elastic limit is the maximum extension at which the spring returns to its original length when the force is removed. If the spring is stretched beyond this, it will be permanently deformed and will not go back to its original length.