A telephone line hangs between two poles 14 m apart in the shape of the catenary , where and are measured in meters.
(a) Find the slope of this curve where it meets the right pole.
(b) Find the angle between the line and the pol

Respuesta :

Answer:

a) At x=14 the slope will be given by:

[tex]\frac{dy}{dx}(14)=a\sinh \left({\frac {14-C_{1}}{a}}\right)[/tex].

b) Then, the angle between the line and the pole will be:

[tex]\phi=\pi - \theta[/tex]

where [tex]\theta[/tex] is the angle between the tangent to the catenary and the x-axis.

Explanation:

The catenary has the following general form:

[tex]y(x)==a\cosh \left({\frac {x-C_{1}}{a}}\right)+C_{2}[/tex]

a) The slope at any point will be given by the derivative of y.

[tex]\frac{dy}{dx}(x)=a\sinh \left({\frac {x-C_{1}}{a}}\right)[/tex]

At x=14:

[tex]\frac{dy}{dx}(14)=a\sinh \left({\frac {14-C_{1}}{a}}\right)[/tex].

b) The angle between the tangent to the catenary and the x-axis at a given point will be given by:

[tex]\frac{dy}{dx}(x)=tan(\theta)[/tex] ⇒ [tex]\theta=tan^{-1} (\frac{dy}{dx}(x))[/tex]

Then, the angle between the line and the pole will be:

[tex]\phi=\pi - \theta[/tex].