# Termial Velocity

1. Jan 20, 2008

### xxneilxx

1. The problem statement, all variables and given/known data
Aim: investigation of how terminal velocity of a parachute is related to the mass it carries and it diameter. object is a cube , height is 10m, diameter will only vary.

2. Relevant equations
I know that F = mg -kv
therfore v = [(2mg/rhoAc_d)]^1/2

3. The attempt at a solution
I am trying to find a simpler way to measure terminal velocity. Any help would be appreciated.

2. Jan 20, 2008

### mgb_phys

Just measure the time taken for the cube to drop the last 10-20cm.
eg. Have the cube sliding down a vertical wire, so you know exactly where it will go, and have two light beam's 20cm apart that the cube will break + an electronic timer.
It might be tricky yo have a wire that doesn;t foul the chute.
Alternative is to paint lines on a background say 5cm apart, near the floor where the cube will land and film it with a digital video camera - then calcualte how far the cube falls in a frame time of the camera.
Or the old fashioned way, do it in the dark with a regular camera and a strobe flash - the digital video is probably easier

3. Jan 21, 2008