A force F at an angle θ above the horizontal is used to pull a heavy suitcase of weight mg a distance d along a level floor at constant velocity. The coefficient of friction between the floor and the suitcase is μ. The work done by the frictional force is ________.(A) -Fd cos θ (B) - µ Fd cos θ (C) -µmgd (D) -µ mgd cos θ

Respuesta :

Answer:

Work done [tex]W=-\mu mgcos\Theta[/tex]

So option (d) will be correct option

Explanation:

We have given that applied force is F

Angle above the horizontal is [tex]\Theta[/tex]

Coefficient of friction is [tex]\mu[/tex]

So frictional force will be equal to [tex]f=\mu mg[/tex]

Distance is given as d

Work done is equal to [tex]W=-\mu mgcos\Theta[/tex] ( Negative direction is due to frictional force as it is a opposing force )

So work done [tex]W=-\mu mgcos\Theta[/tex]

So option (d) will be correct option