Which of the following best describes the movement of a falling object?
a.it moves with a uniform speed
b.it moves with a reducing speed
c.it moves with an increasing speed
d.It moves with a uniform speed and then with an increasing speed.
The best way to determine the movement of a falling object is by considering the forces acting upon it. In this case, we need to consider two main forces: gravity and air resistance.
At the beginning of the fall, when the object has just been released, gravity is the dominant force and air resistance is negligible. This means that the object will initially accelerate due to gravity, and its speed will increase. So, option c - "It moves with an increasing speed" - is the correct answer.
However, it's important to note that after a certain point, as the object's speed increases, the air resistance acting upon it will also increase. At a certain point, the air resistance will become equal to the force of gravity, resulting in a condition known as terminal velocity. At terminal velocity, the object will no longer accelerate and will continue to fall with a constant speed. This speed is determined by the balance between gravity and air resistance.
Therefore, option d - "It moves with a uniform speed and then with an increasing speed" - would accurately describe the movement of a falling object once it reaches terminal velocity. However, it's worth mentioning that this occurs after an initial period of increasing speed.
accelerated by gravity
until air resistance equals gravitational force