Why is 1.2g the Hypotenuse on an Inclined Plane?

[Jamie Bristow]

Homework Statement

When resolving forces on an inclined plane, can anyone explain to me why 1.2g in my pic is used as the hypotenuse? It looks intuitively like it should be the opposite or adjacent.

Thanks for any help :)

Homework Equations

The Attempt at a Solution

 

[Doc Al]

Whenever you resolve a vector into components that vector will be the hypotenuse. (Don't confuse the triangle of the inclined plane with the triangle you need when resolving a vector.)

 

[Doc Al]

Read this: Inclined Planes

 

[Jamie Bristow]

Thank you