Question

A dropped ball accelerates as it falls. but a ball rolling on a horizontal surface has zero acceleration because _______.

Answer 1

There is no force acting on it.

Step-by-step explanation:

The dropping ball experiences the force of gravity on it that make sit accelerate towards the ground constantly, if the ball is rolling on a horizontal surface the effect of the gravity will just have an effect on the weight of the ball and the friction, but unless you are applying an external continuos force to that ball it would not experience acceleration.

Answer 2

During a fall, the ball experiences an external force which is acted upon by gravity. This gravitation force induces a constant gravitational acceleration on the object equivalent to 9.81 meters per square second. Hence, the dropped ball is accelerating.

On the other hand, the ball does not experience external force hence the acceleration is zero.