Free body diagrams and equilibrium

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Please can someone explain how to do question 2?

Resolve weight of the object into 2 components
a) one parallel to the surface
b) one perpendicular to the surface

If the object isn't moving then the forces are balanced.

This means in a) the component is equal to the frictional force
b) the component equals the normal reaction.


The other question you posted is done the same way.

I really don't understand how to do this, please could you explain a bit more?

What don't you understand?
Do you not know how to resolve a force into two components? ( sin and cos of the angle?)

I know you use sin and cos but i don't know what angle you use?