Atire hanging from a tree is at rest. the force of gravity is pulling down on the tire. another force, called tension, is pulling up on the tire. tension is the pulling force that is transferred along the length of a string or rope.
picture below
if the force of tension is equal to the force of gravity, then
a. the tire will swing toward the left.
b. the tire will remain at rest.
c. the tire will accelerate upward.
d. the tire will accelerate toward the ground. reset

B. the tire will remain at rest.  

Explanation:

According to Newton's first law, an object changes its state of rest or motion when an unbalanced external force acts on it. In the given situation, the tire will remain at rest because the net force acting on the tire is balanced. The force of tension pulling up the tire is equal to gravitational force acting downwards. The two forces are equal and in opposite direction balancing each other.

frequency or wavelenth of em radiation in a vacuum

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