If a ball is accelerating down through the air with no horizontal motion what must be true about the net forces acting on the ball
If a ball is accelerating down through the air with no horizontal motion, it means that the net force acting on the ball must be directed downward. This downward net force is greater than the force of gravity acting on the ball alone, which causes the ball to accelerate in the downward direction.
If a ball is accelerating down through the air with no horizontal motion, then the net force acting on the ball must be directed downward, opposite to the direction of its motion. This net downward force is responsible for the acceleration of the ball. In the absence of any horizontal motion, there is no net force acting in the horizontal direction.
To determine what must be true about the net forces acting on the ball, we can start with Newton's second law of motion, which states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.
In this case, the ball is accelerating downward through the air. Since there is no horizontal motion, we can ignore any forces acting in the horizontal direction. We are only concerned with the forces acting vertically.
If the ball is accelerating downward, it means there must be a net force acting downward. This force is responsible for overcoming any opposing forces and causing the ball to accelerate.
Considering the forces acting on the ball in the vertical direction, we have two main forces: gravity and air resistance (also known as drag).
Gravity always acts downward towards the center of the Earth. It is a force that pulls objects towards the ground and can be calculated as the mass of the ball multiplied by the acceleration due to gravity (9.8 m/s²).
Air resistance, on the other hand, acts in the opposite direction of the ball's motion through the air. When an object moves through the air, it experiences a resistance force due to the friction between the object and the air molecules. Air resistance depends on various factors such as the shape of the object, its velocity, and the density of the air.
In this situation, if the ball is accelerating downward with no horizontal motion, it means that the force of gravity must be greater than the force of air resistance. This is because the net force acting on the ball is the vector sum of all the forces acting on it. If gravity is stronger than air resistance, the net force will be downward, resulting in the ball's acceleration.
To summarize, for a ball accelerating down through the air with no horizontal motion, the net force acting on the ball must be downward, meaning that gravity must be greater than air resistance.