Respuesta :

Answer: 215.15 N

Explanation:

If we draw a free body diagram of the mass we will have the following:

[tex]\sum{F_{x}}=-Tcos\theta + F=0[/tex] (1)

[tex]\sum{F_{y}}=Tsin\theta - mg=0[/tex] (2)

Where [tex]T[/tex] is the tension force of the rope, [tex]m=28 kg[/tex] the mass, [tex]g=9.8 m/s^{2}[/tex] the acceleration due gravity and [tex]mg[/tex] is the weight.

On the other hand, we can calculate [tex]\theta[/tex] as follows:

[tex]cos\theta=\frac{s}{l}[/tex]

[tex]\theta=cos^{-1}(\frac{s}{l})[/tex]

Where [tex]s=11.1 m[/tex] and [tex]l=18 m[/tex]

[tex]\theta=cos^{-1}(\frac{11.1 m}{18 m})[/tex]

[tex]\theta=51.9\°[/tex] (3)

Now, we firstly need to find [tex]T[/tex] from (2):

[tex]T=\frac{mg}{sin\theta}[/tex] (4)

[tex]T=\frac{(28 kg)(9.8 m/s^{2})}{sin(51.9\°)}[/tex]

[tex]T=348.69 N[/tex] (5)

Substituting (5) in (1):

[tex]F=Tcos\theta[/tex] (6)

[tex]F=348.69 N cos(51.9\°)[/tex]

Finally:

[tex]F=215.15 N[/tex]