Question

A 60 N weight is Supported by a cable attached to an end of a light rod, whose other end is hinged at point P. The rod is supported by a second cable as shown. The force exerted by the hinge on the rod has magnitude.

• A. 42 N
• B. 30 N
• C. 60 N
• D. 51 N

Answer 1

Answer: (A)

42 N

Answer 2

Suppose N is the normal induced in the rod, then it is also equal to force exerted by the hinge on the rod. For horizontal equilibrium

T cos 45⁰ = N cos 45⁰ ⇒ T = N

For vertical equilibrium

2N cos 45⁰ = 60

⇒ N = 42N