Vectors as forces question: A 10 kg block lies on a smooth ramp that is inclined at 30 degrees... A 10 kg block lies on a smooth ramp that is inclined at 30 degrees. What force, parallel to the ramp, would prevent the block from moving? (Assume that 1 kg exerts a force of 9.8 N)
You need to figure out what are the forces acting on the block. The gravity force acts on the block and it is orthogonal to horizontal axis.
The gravity vector makes an angle of `30^o` to the normal axes to inclined ramp, that passes through centroid of the body.
You need to find horizontal component of gravity force vector, such that:
`F_x = G*cos 60^o`
`F_x = 10*9.8*(1/2)`
`F_x = 49 N`
Hence, evaluating the force that stops the body to move, neglecting the friction force, yields `F_x = 49 N` .
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