Question

A 7.30 kg sign hangs from two wires. The

Answer 1

Answer:

$28.0\; {\rm N}$ to the right.

Explanation:

Since the sign is not moving, the net force on this sign should be $0\; {\rm N}$. For that, the horizontal component ($x$-component) of external forces on this sign should be $0\; {\rm N}$.

Sources of external forces on this sign include tension from the wires, as well as gravitational pull (weight) from the earth. The gravitational pull from the earth is entirely vertical ($y$-component,) with a magnitude of $0\; {\rm N}$ in the horizontal direction. Thus, the only external forces on this sign in the $x$-component would be from the two wires.

The question states that the $x$-component of the force from the first wire is $28.0\; {\rm N}$ to the left. Thus, for the net force in the $x$-direction to be $0\; {\rm N}$, the force from the other wire in the $x\!$-component needs to be $28.0\; {\rm N}\!$ to the right (same magnitude but opposite direction.)