# Length of Guy Wire

• Sep 2nd 2008, 06:51 AM
magentarita
Length of Guy Wire
A radio transmission tower is 200 feet high. How long should a guy wire be if it is to be attached to the tower 10 feet from the top and is to make an angle of 21 degrees with the ground?

• Sep 2nd 2008, 07:14 PM
horseypie
Draw a picture mate...draw a line depicting the tower vertically and label it as 200feet high, then make a right angled triangle, with the hypotenuse representing the guy wire and the horizontal line representing the ground.

Now since the wire is connected 10 feet from the top of the tower the triangle you really have has a height of 190 feet, a hypotenuse of length 'x' (what you're trying to find) and the angle the wire makes with the ground is 21 degrees. From this, which trig. ratio (sin, cos, tan) allows you to relate the side opposite the angle (from the picture) to hypotenuse?
• Sep 2nd 2008, 09:58 PM
magentarita
Great
Quote:

Originally Posted by horseypie
Draw a picture mate...draw a line depicting the tower vertically and label it as 200feet high, then make a right angled triangle, with the hypotenuse representing the guy wire and the horizontal line representing the ground.

Now since the wire is connected 10 feet from the top of the tower the triangle you really have has a height of 190 feet, a hypotenuse of length 'x' (what you're trying to find) and the angle the wire makes with the ground is 21 degrees. From this, which trig. ratio (sin, cos, tan) allows you to relate the side opposite the angle (from the picture) to hypotenuse?

I thank you for the tips.