Calculate Velocity of Skydiver: Mass M, Air Drag Coefficient D

In summary, the conversation discusses the calculation of the velocity of a skydiver with a mass of 80kg as a function of time, taking into account the air drag coefficient of 0.1kg/m. The speaker mentions finding a velocity of 88.5 m/s using the formula for high-speed air drag, but notes that this is not the desired velocity. They then mention using a formula derived from low-speed air drag, but are unsure of the exact formula. They ask for assistance and a link is provided to a page explaining the theory and derivation of the formula for terminal velocity.
  • #1
Crebble32
7
0
Calculate velocity of the skydiver of mass M= 80kg as a function of time. The air drag coefficient D= 100g/m = 0.1kg/m. Assume that the skydiver has v=o at t=0.


In my book high speed air drag is f=Dv^2.
I found Vt= 88.5 m/s with Sqrt(mg/D). BUT this is not the V they are asking for :(

my book derives the formula for V with the low speed air drag, not the HIGH speed one. I can't follow the steps they did and figure out what exactly the formula actually is! What I started out with is:

m*(dv/dt) = mg- Dv^2

I have no clue where to go from here :( If anyone could help me I appreciate any help I can get!
 
Physics news on Phys.org
  • #3
Thank you so much!
 

1. How do you calculate the velocity of a skydiver?

The velocity of a skydiver can be calculated using the formula v = v0 + gt, where v is the final velocity, v0 is the initial velocity, g is the acceleration due to gravity, and t is the time elapsed.

2. What is the mass of the skydiver?

The mass of the skydiver is an important factor in calculating their velocity. It can be measured in kilograms (kg) and is typically around 70-90 kg for a person.

3. What is the air drag coefficient?

The air drag coefficient, represented by the symbol D, is a measure of the amount of air resistance that the skydiver experiences during their fall. It depends on factors such as the shape and size of the skydiver, as well as their orientation and speed.

4. How does air resistance affect the velocity of the skydiver?

Air resistance, or drag, acts in the opposite direction to the motion of the skydiver and increases as their velocity increases. This means that as the skydiver falls faster, the air resistance also increases, eventually reaching a point where it balances out the force of gravity, resulting in a constant terminal velocity.

5. Can the velocity of a skydiver be changed during their fall?

Yes, the velocity of a skydiver can be changed by altering their body position. By creating a more streamlined shape, the skydiver can decrease their air drag coefficient and increase their velocity. Conversely, by spreading out their body and increasing their drag, they can slow down their descent.

Similar threads

Final Velocity of a car with a opposing decreasing drag force
    • Introductory Physics Homework Help
2
Replies
57
Views
639
Motion of a Parachuter (Terminal Velocity, Time of Flight, Distance)
    • Introductory Physics Homework Help
Replies
10
Views
291
Effect of Surface Area on the Drag Coefficient of a Parachute
    • Introductory Physics Homework Help
Replies
6
Views
2K
Drag coefficient experiment
    • Introductory Physics Homework Help
Replies
6
Views
1K
Velocity of a football with and without drag
    • Introductory Physics Homework Help
Replies
7
Views
2K
How do I find the terminal speed of a body in water?
    • Introductory Physics Homework Help
Replies
13
Views
3K
Finding the sum and difference of two drag coefficients
    • Introductory Physics Homework Help
Replies
5
Views
1K
Calculating Drag Coefficient from Wind Tunnel Data
    • Introductory Physics Homework Help
Replies
3
Views
2K
I Drag Coefficient of a 'flexible' object (e.g. a piece of paper)
    • Mechanics
Replies
4
Views
340
Dimensions of Air Drag Constants and Terminal Speed Equation
    • Introductory Physics Homework Help
Replies
15
Views
1K

Hot Threads

Recent Insights

Back
Top