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7. Friction forces

Why do we use studded snow tyres on
cars in the winter? In Unit 6 you learnt:

✔ about different kinds of deformation Physics
textbooks nis edu kz
✔ that Hooke’s Law is applied only to
elastic deformations
✔ the difference between elastic and
plastic deformations

In this unit you will learn:

✔ about different kinds of friction

✔ the reasons why friction forces occur
✔ the role of friction in our daily lives

Key phrases:

✔ To reduce sliding friction …

✔ To increase friction it is necessary to …
✔ Sliding friction force depends on …
and does not depend on …

✔ Rolling friction force appears …

CCL From your Maths classes you are familiar
with the concept of vector. This knowledge will
help you to calculate resultant force.

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