A rectangular shop sign of mass 12 kg is hung from the ceiling by two light cables…
PHYSICS · Multi-part · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
A rectangular shop sign of mass 12 kg is hung from the ceiling by two light cables attached to its upper corners. The left-hand cable is fixed to the ceiling such that it makes an angle of 25° with the horizontal, while the right-hand cable makes an angle of 65° with the horizontal. The sign hangs motionless.
(a) Draw a clearly labeled free-body diagram for the sign, showing all external forces acting on it.
(b) Explain whether the magnitudes of the tensions in the two cables must be equal or unequal. Base your reasoning on appropriate principles of mechanics.
(c) Without performing detailed numerical calculations, rank the magnitudes of the following three forces from greatest to least and justify your ranking: the weight of the sign, the tension in the left cable, and the tension in the right cable.