Question

If the acceleration of an object is zero, are no forces acting on it? Explain.

Short answer

There might be forces acting on the object, but the summation of those forces must be zero.

Step-by-step solution

Step 1. Relation between the net force on an object and its acceleration

According to Newton’s second law, the net force acting on the object is directly proportional to its acceleration.

Step 2. Applying Newton’s second law on the object with zero acceleration

According to Newton’s second law, you know that acceleration is directly proportional to force and follows the relation

$F=ma$.

Here, m is the mass of the object, F is the net force applied, and a is the acceleration.

Thus, from the above relation, you can conclude that if the object does not experience any acceleration, it means the net force on that object must be zero.

Moreover, it also means that even though forces may be acting on that object, yet the summation of those forces is zero.