A block of mass of 2 kg slides on an inclined plane that makes an angle of `30^(@)` with the horizontal . The coefficient of friction between the block and the surface is `sqrt(3)//2` .
What force should be applied to the block so that it moves up without any acceleration ?

Explanation

Mass of the block , m = 2kg
Angle of inclination , `theta=30^(@)`
Coefficient of friction between the block and the surface , `mu=(sqrt(3))/(2)`
The required force to move the block down without acceleration is

`F=mg(sintheta-mu_(k)costheta)`
=`2xx9.8(sin30^(@)-(sqrt(3))/(2)xxcos30^(@))`
`=2xx9.8((1)/(2)+(sqrt(3))/(2)xx(sqrt(3))/(2))=24.5N`