Final answer:
When the net force on an object is zero, it could either be at rest or moving at a constant velocity. This is in accordance with Newton's First Law of Motion. A stationary book or a car moving at a steady speed are examples.
Step-by-step explanation:
The statement that when the net force on a body is zero, the body may be in a state of motion as well as in a state of rest is true.
This is derived from Newton's First Law of Motion, which states that an object will continue its state of motion or rest unless a net force acts on it. If the net force on a body is zero, it indicates that there is either no force acting on it, or the sum of all acting forces are balanced, causing no change in its motion. Therefore, the body could either be at rest or moving at a constant velocity.
For instance, if a book is at rest on a table, the forces acting on it (gravity and the normal force from the table) are equal and opposite, creating a net force of zero. Similarly, a car moving at a constant speed on a straight road experiences a net force of zero as the forces of friction and the engine thrust balance out.
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