# Thread: Tension in the wire

1. ## Tension in the wire

A mass of 50 Kg is suspended from the top in of the pole that is inclined 40 degrees to the vertical. the end of the pole is supported by a wire that is making an angle of 75 degrees with the pole.
What is the tension in the wire?

http://img833.imageshack.us/img833/1038/diagramxf.png

2. ## Re: Tension in the wire

Originally Posted by Clairvoyantski
A mass of 50 Kg is suspended from the top in of the pole that is inclined 40 degrees to the vertical. the end of the pole is supported by a wire that is making an angle of 75 degrees with the pole.
What is the tension in the wire?

http://img833.imageshack.us/img833/1038/diagramxf.png
Let length of pole = L
Taking moments about the foot of the pole T*Lsin75=50*Lsin40

3. ## Re: Tension in the wire

Can you elaborate?

4. ## Re: Tension in the wire

The moment of a force about a point is the product of the force and the perpendicular distance from the point to the line of the force. When a system is in equilibrium the sum of clockwise moments = the sum of anticlockwise moments

5. ## Re: Tension in the wire

What do I do next?
Thanks and Regards,

6. ## Re: Tension in the wire

... click on the sketch

7. ## Re: Tension in the wire

Yes, but then I dont know the value of L!

8. ## Re: Tension in the wire

Originally Posted by Clairvoyantski
Yes, but then I dont know the value of L!
you don't need the value of L ... its value cancels out as it is a common factor on both sides of the equation.

LOOK at the equation on the sketch once again.