Question

You are using a lightweight rope to pull a sled along level ground. The sled weighs 485 N, the coefficient of kinetic friction between the sled and the ground is 0.200, the rope is at an angle of 12∘ above the horizontal, and you pull on the rope with a force of 125 N. Find the normal force that the ground exerts on the sled.

Answer 1

Answer:

$N=459.01N$

Explanation:

According to Newton's first law:

$N+F_y-W=0$

The component of the force on the y-axis can be obtained through the Pythagorean Theorem. This is because the components are the cathetus of a right triangle and its hypotenuse is the magnitude of the force:

$sin12^\circ=\frac{F_y}{F}\\F_y=Fsin12^\circ$

Replacing and solving for N:

$N=W-Fsin12^\circ\\N=485N-(125N)sin12^\circ\\N=459.01N$