How does air resistance affect the acceleration of a falling object?

Answer 1

Air resistance causes a force that opposes the motion. So the falling object will accelerate less and less until it finally hits terminal velocity. At that point, the air resistance equals the weight, so there is no net force, and the velocity is constant from there on out.

Answer 2

Of course it does.

As an object falls from a height the air pressure differs; the longer the drop the greater the difference in acceleration due to air resistance.

That's why the acceleration due to gravity is measured at sea level, to account for the air pressure. This value is used universally because it is close enough. To be exact though a function will have to be written that describes the value of air resistance across the entire distance of the fall.

When a classic physics problem is proposed involving acceleration usually the speeds are high enough that things like air resistance can be ignored. Of course if you are doing rocket design then you can’t ignore this resistance, nor can you ignore it if you are calculating the speed of a fast moving car. Racecars and sports cars are designed to stay on the road. They have a wing design that is flipped upside down so instead of getting lift the car gets down pressure thus holding it to the road. When you are figuring the drag on the car you need to account for air resistance as well. Not the change as the car falls from a height, but the change as the air has to be pushed out of the way as the car goes faster. This is what aerodynamics is all about.

To make matters worse the air resistance to a falling object changes over the distance of the fall, so you can only determine the acceleration of the object at certain points. To determine the actual acceleration you need calculus, which is why after Newton invented physics, he had to invent calculus to use physics. F=ma is valid, but it is a changing value that can only be described with calculus.

Answer 3

from newtons second law

F = ma

so when the object is falling...ignoring air resistance...the force of gravity is the only force acting on it...so...

F_g = mg

notice here the acceleration is the acceleration of free fall, g
now if u have resistive forces...it opposes the force of gravity...let it be F_r....so

F_r = m* a_r

where a_r is the acceleration of the falling body due to the resitive force. since F_g and F_r are opposing each other...the net force F is

F = F_g - F_r = mg - m*a_r = m*(g - a_r)

so u see...the net force on the falling body decreases...and so does the acceleration....this is the cause of the *weightlessness* feeling when u sky dive...because the net force on u decreases...at a certain point....a_r rises and equals g....in which case F_g equals F_r...so there is no net force on u....and u feel as if u are in a no gravity zone!....at that point u are falling to the ground at a constant velocity known as the terminal velocity (constant velocity = 0 acceleration)

Answer 4

The acceleration of a falling body is constant at 9.8m/s^2. Air resistance (i.e. "Drag") is a Force (not unlike a friction force of a sliding mass) that varies as the square of the velocity. As the velocity (drag) increases, there will be a balance of forces (Weight vs Drag) where the mass will achieve a steady state velocity.

Answer 5

It lowers the acceleration and reduces the terminal velocity or the velocity where the acceleration stops.

Answer 6

air resistance will reduce the mechanical energy(the sum of gravitational potential energy and the kinetic energy)
of the object.
for example, the rain drops from thousands miles high .without air resistance, it would be able to penetrate your roof or your head.

Answer 7

explain why an astronaut in an orbiting spaceship floats?