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Search found 1232 matches

by James9118
Sat Feb 09, 2013 4:51 pm
Forum: Flycasting Physics
Topic: SHO and forces
Replies: 49
Views: 16047

SHO and forces

Hi Gordy,

My spreadsheet will produce this exact same result, however I don't think it needs the forces either side of the spring to be different in order to do so. A plot of F2 and F3 would really help me as I'm assuming they are the same.

Thanks, James.
by James9118
Sat Feb 09, 2013 4:34 pm
Forum: Flycasting Physics
Topic: SHO and forces
Replies: 49
Views: 16047

SHO and forces

Gordy,

Thanks for your response. Could you please plot an overlay of F2 and F3 with time please, this will help me understand things.
My spreadsheet solves for position by the way, I then calculate force from the spring constant (k) and spring deflection (x).

James.
by James9118
Sat Feb 09, 2013 9:01 am
Forum: Flycasting Physics
Topic: SHO and forces
Replies: 49
Views: 16047

SHO and forces

Merlin,

I think I'm beginning to understand Walter's frustration here, perhaps I don't understand the model I've got. If that is the case can you tell me the circumstances in which F2 does not equal F3?
by James9118
Sat Feb 09, 2013 8:49 am
Forum: Flycasting
Topic: Axial torque improves distance?
Replies: 25
Views: 12723

Axial torque improves distance?

If I point at my stop point with my index finger and then quickly rotate my hand, I find that I'm pointing at a new spot. I can imagine the effect on the rod tip from this could be quite large. So is it down to giving the (normal) rotational acceleration a boost very late in the stroke? (nothing to ...
by James9118
Thu Feb 07, 2013 6:28 pm
Forum: Flycasting Physics
Topic: SHO and forces
Replies: 49
Views: 16047

SHO and forces

F2(t) = F3(t) for t in the range of 0 to infinity (don't know what was going on before the big bang :D )
by James9118
Tue Feb 05, 2013 5:41 pm
Forum: Flycasting Physics
Topic: Spanish experiment
Replies: 147
Views: 39121

Spanish experiment

This has been posted before but I thought I'd put it up again as it predicts the 'tuning' behaviour seen in Alejandro's experiment. Maximum 'mass' velocity in blue, whereas the red line denotes the max velocity of the drive (again with the usual caveat that this is a set of drive conditions defined ...
by James9118
Fri Feb 01, 2013 7:04 pm
Forum: Flycasting Physics
Topic: Spanish experiment
Replies: 147
Views: 39121

Spanish experiment

James Your plots show that velocity for the drive becomes zero at roughly .47 seconds and roughly .53 seconds but your plot of position for both clearly shows that they continue on in a positive direction for some time and then begin to return after that. How do you account for the objects continui...
by James9118
Fri Feb 01, 2013 6:39 pm
Forum: Flycasting Physics
Topic: Spanish experiment
Replies: 147
Views: 39121

Spanish experiment

Hi Aitor,

If you are filming is there any chance you can put some markings on the table so positional and velocity measurements can be made?
by James9118
Fri Feb 01, 2013 5:58 pm
Forum: Flycasting Physics
Topic: Spanish experiment
Replies: 147
Views: 39121

Spanish experiment

Picking up on what Gordy is saying with regard to acceleration, velocity and position: Here is a model output that we've seen many times before, the velocity vs. time for a fixed link and a spring/mass combination. mass drive.jpg As you can read from the graph, the time at which the 'mass' velocity ...
by James9118
Thu Jan 31, 2013 10:42 pm
Forum: Flycasting Physics
Topic: Spanish experiment
Replies: 147
Views: 39121

Spanish experiment

Hi Lasse, I was once sat at the traffic light in my home town with a police car behind me. I accelerated off in my usual, slightly heavy right footed, way. I got to 30mph, backed off and maintained that speed. A few moments later the blue lights came on and I was pulled over. The police woman accuse...

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