Answer:
The the angle which the wire make with the ground is 1.280 radian .
Step-by-step explanation:
Given as :
The length of the wire attached to the top of building = OB = 70 foot
The distance of wire anchored from base of ground = OA = 20 feet
Let the angle made by wire en and ground = Ф
Now from , In Triangle AOB
Cos angle = [tex]\dfrac{\textrm Base}{\textrm Hypotenuse}[/tex]
Or, Cos Ф = [tex]\dfrac{\textrm OA}{\textrm OB}[/tex]
or, Cos Ф = [tex]\dfrac{\textrm 20}{\textrm 70}[/tex]
Or, Cos Ф = [tex]\dfrac{\textrm 2}{\textrm 7}[/tex]
∴ Ф = [tex]Cos^{-1}(\frac{2}{7})[/tex]
I.e Ф = 73.39°
Now in radian ,
∵ 180° = [tex]\pi[/tex] radian
∴ 73.39° = [tex]\frac{\pi }{180}[/tex] × 73.39°
= [tex]\frac{3.14 }{180}[/tex] × 73.39° = 1.280 radian
Hence The the angle which the wire make with the ground is 1.280 radian . Answer
