Calculating Tension in Cables for 17.0 kg Speaker

[kappcity06]

A loudspeaker of mass 17.0 kg is suspended a distance of h = 1.80 m below the ceiling by two cables that make equal angles with the ceiling. Each cable has a length of l = 3.30 m.

What is the tension in each of the cables?

Tried mg sintheta^2+mgcostheat^2=c^2 but no dice.

Anyone know anything?

thanks

 

[Dick]

The tension forces point along the wires. Call their magnitude T and split them into horizontal and vertical components. The horizontal components cancel and the sum of the vertical components should cancel the mg force on the speaker.

 

[andrevdh]

The two (similar in magnitude tensions) and the weight form a triangle. If theta is the angle between the cables and the ceiling then the angle between the two tension vectors in the triangle is two times theta.