Final answer:
The state of equilibrium of an object does not depend on whether the number of forces is odd or even, but on whether the net force acting on the object is zero, demonstrating that the claim in the student's question is false.
Step-by-step explanation:
The statement "If an odd number of forces act on an object, the object cannot be in equilibrium" is false. The state of equilibrium of an object depends on the net force acting upon it, not the number of forces.
According to Newton's First Law, an object is in equilibrium if the net force acting on it is zero, which means that the forces are balanced, regardless of whether they are odd or even in number.
Example: Consider a book resting on a table where three forces act upon it - gravitational force downward, normal force upward by the table, and a upward lifting force by your hand. If the downward gravitational force is equal to the sum of the two upward forces by your hand and the table, the book will remain at rest in equilibrium although three forces are acting on it.
A point is in equilibrium if the forces acting on it have equal magnitudes but opposite directions, and in a tug-of-war, when the rope snaps, the forces become unbalanced, causing each team to move backwards.