# Homework Help: Help With Lift And Drag Forces On A Ball, Bernoullis Principles.

1. May 7, 2012

### imamul

1. The problem statement, all variables and given/known data
Any help would be appreciated, whether that is formulas or working out.
Questions
For each of the vertical levitation examples calculate the lift force exerted on the ball.

For each of the inclined levitation examples calculate the lift and drag forces exerted on the ball.

BeachBall, Circumference = 73cm, Weight = 100g

Velocities At Different Points On The BeachBall at 90 degrees, From Far Left To Far Right:
A1: 0.5 m/s
B1: 5 m/s
C1: 13.5 m/s
D (center): 15.5 m/s
A2: 0.4 m/s
B2: 5.1 m/s
C2: 10.5 m/s

Velocities At Different Points On The BeachBall at 45 degrees, From Far Left To Far Right:
A1: 0.1 m/s
B1: 2.2 m/s
C1: 7.6 m/s
D (center): 11.2 m/s
A2: 0 m/s
B2: 2.5 m/s
C2: 7.2 m/s

2. Relevant equations
Dont know, have attempted to find.

3. The attempt at a solution
Formula used:
F=(1/2)Pv^2CA
P=density
A=cross section
v=velocity
c=drag coefficient

CD=2FD/PV^2A

CD=2FD/110 x 11.2^2 x424

A= Pi r^2
Diameter = 23.23
R= 11.615

Last edited: May 7, 2012