A 30 kg block is to be moved up an inclined plane at an anglue 30° to the horizontal with a velocity of `5ms^(-1)`. If the frictional force retarding the motion is 150N find the horizontal force required to move the block up the plane. (`g=10ms^(-2)`)

Explanation

The force required to a body up an inclined plane is
`F=mg sin theta+` frictional force
`= 30(10)sin 30^(@)+150=300N`. If P is the horizontal force, `F=P cos theta`
`P=(F)/(cos theta)=(300)/(cos theta)=(300xx2)/(sqrt(3))`
`= 200sqrt(3)=346N`.