Air Resistance Formula
Air Resistance Formula
There is a resistive force associated with every sort of motion in the world. In physics, this form of resistive force is referred to as resistance. A body will experience resistance when passing through any media other than a vacuum, and air is no exception. The friction that bodies experience when travelling through air is referred to as air resistance or drag. This Physics article will explain the air resistance formula and provide some solved cases.
What is Air Resistance?
Air resistance is defined as the friction that bodies experience when travelling through air. Because air contains particles in random motion, any object moving at a specific velocity must overcome the opposing motion of the air particles. Air resistance refers to the accumulated opposed force exerted by the air particles.
For example, if there was no air resistance to overcome, aeroplanes could have turned off their engines once reaching altitude since there would be no opposing force and their speed would not have dropped according to Newton’s equations of motion. Due to the presence of air resistance, aeroplanes must utilise engines when flying.
Air Resistance Formula
Air resistance is the force that air applies to objects moving through it. Scientists frequently refer to this force as “drag” or “drag force.” Usually, this force is generated to slow down the object’s speed by acting in the opposite direction. The moving body is subject to the frictional force of air resistance. Air resistance slows a moving body down. The body experiences higher air resistance the more it moves. The Air Resistance Formula affects all moving objects, including bicycles, cars, trains, rockets, aeroplanes, and even living things.The Air Resistance Formula can be applied to find the air resistance.
The air resistance formula can be mathematically stated as :
Fair = cv2 |
Where,
F = Air resistance or Drag
ρ = Density of the air
CD = Drag coefficient
A = Area of cross section
v = Relative Velocity of the object with air
c = force constant
Solved Examples on Air Resistance Formula
Example 1. The air resistance constant’s value is 0.02. The object’s relative velocity is 80 metres per second. Calculate the drag.
Solution 1: Since the formula for drag is equal to –
Fair = cv2
c = 0.02
Relative velocity = 80 m/s.
Drag = Fair =0.02×(80^2)
Fair =0.02×6400
Fair = 128N
Example 2. An A object is travelling at 140 m/s through the air. In the other direction, air travels at 120 metres per second. The frictional air coefficient equals 0.03. Find the drag.
Solution : Relative velocity of the object = speed of the object – speed of the sir
140−120
= 20 m/s.
Frictional air coefficient = 0.03
Fair =0.03×(20^2)
Fair =0.03×400
Fair =12N
FAQs (Frequently Asked Questions)
1. How do you calculate air resistance?
The air resistance is calculated by the formula-
$$F_{air}= cv^2 = \frac{1}{2} \rho C_{D} A v^2$$
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2. What is called air resistance?
Air resistance is the friction that bodies suffer when moving through the air.
3. State an example of air resistance
The parachute operates because of air resistance, in which the opposing force of the air trapped beneath the parachute reduces the velocity of the body attached to the parachute.
