To stop an object that is falling, you need to counteract its downward motion and bring it to a complete stop. The force required to stop the object depends on the object's mass and the acceleration due to gravity. It does not directly involve the normal force.
When an object falls, it experiences a force known as its weight, which is equal to the product of its mass (m) and the acceleration due to gravity (g). The weight is given by the formula:
Weight = m * g
To stop the object, you need to apply an equal and opposite force to counteract its weight. This force is known as the stopping force. According to Newton's second law of motion, the force required to stop the object is equal to the product of its mass and the acceleration necessary to bring it to a stop:
Stopping force = m * a
Here, 'a' represents the acceleration required to stop the object, which would be in the opposite direction to its initial acceleration due to gravity.
The normal force comes into play when the object is initially at rest and being held up against gravity. It is the force exerted by a surface to support the weight of an object. In this case, the normal force cancels out the weight of the object, resulting in a net force of zero. However, once the object is released and falls, the normal force does not contribute directly to stopping it. The stopping force required is solely determined by the object's mass and the acceleration needed to bring it to rest, as explained above.