PHYSICS
posted by Ann on .
1)A picture of width 40 cm weighing 40N hangs from a nail by means of flexible wire attached to the sides of the picture frame. The midpoint of the wire passes over the nail which is 3 cm higher than the points where the wire is attached to the frame. Find the tension of the wire.

the wire on each side supports mg/2
Looking at the force diagram, sinTheta(angle of depression)=(mg/2)/Tension
but tanTheta=3/20 according to the dimensions.
Tension= 20/sinTheta= 20 /sin(arctan.15) 
Thank YOu!