Question

(a) What do you understand by the terms "balanced forces" and "unbalanced forces"? Explain with examples.
​(b) What type of forces - balanced or unbalanced - act on a rubber ball when we press it between or hands? What effect is produced in the ball?

Answer 1

(a) Balanced forces: When two or more forces act on an object but are not able to change the state of rest or of motion of that object, the forces are called balanced forces. The resultant of balanced forces is always zero, so they can not produce any acceleration in the object.

Example: If more than two people push a box from different sides and the box does not move, that means the forces are balanced.

Unbalanced forces: When two or forces act on an object and are able to change the state of rest or of motion of that object, the forces are called unbalanced forces. Unbalanced forces always have a resultant and can produce an acceleration in the object.

Example: If few people push a box from different directions and the box starts moving then the forces acting on the object are unbalanced forces.

(b) When we press a ball between our hands, then the forces acting on the ball are balanced, as they do not cause any motion to the ball. When we press the ball between our hands, the ball gets compressed or deformed. The balanced forces change the shape of the ball.