Question

When a block is sliding down a inclined plane that has the angle 30° and there is no friction what is the acceleration of the block?

Answer 1

what force is responsible for the acceleration of the block ?

Answer 2

it isnt given.

Answer 3

that's because you can say what it is from common sense : )

Answer 4

So the asnwere is just 9,8 m/s^2 , because the two forces up and down cancel out?

Answer 5

I'm not sure what you mean that the up and down forces cancel - the acceleration due to gravity is what makes the block slide down the inclined plane, and this acts vertically downward, so you need to calculate the component of this acceleration along the direction of the inclined plane
This is easy because you are given the angle of the incline

Answer 6

aaa okei im just kidding :) .. so it must be 9,8sin30 = 4,9 m/s^2