3 A picture is supported by two vertical strings; if the weighi of the picture is 50 N what is the force exerted by each
string ?

The force exerted by each string is 25 N

Explanation:

Net Force

The net force is the vector sum of forces acting on a body. The net force is a single force that represents the effect of the original forces on the body's motion. It gives the particle the same acceleration as all those actual forces together as described by Newton's second law of motion.

The picture described in the problem is hanging at rest supported by two vertical strings. This means that the net force acting on it is zero.

Assume the magnitude of each of these equal forces is F, and the picture has a weight of W=50 N, thus the net force is:

F + F - W

The positive signs indicate an upwards direction and the negative sign means a downwards direction. Since the net force is zero:

F + F - W = 0

2F = W

F = W/2 = 50 N/2

F = 25 N

The force exerted by each string is 25 N

the entire statement is true and correct.  

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