force or velocity

[logix1390]

hello,

What exactly is the difference between a force and velocity? Is there anything I should read up on? I noticed that my flip sim acts differently to an @force attribute vs @v 

Thank you

[flcc]

Velocity is the result of initial conditions and interactions (including forces)
Forces influence speed, not the other way around.
This is why, if in a wrangle for example, we want to act on speed, we will write : v@v += something;
If we write v@v = something; we will cancel the effect of all forces.

[isah_voodoo]

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Edited November 4, 2019 by isah_voodoo

[isah_voodoo]

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Edited November 4, 2019 by isah_voodoo

[logix1390]

@flccSo if velocity is speed and direction,  and force is just influencing the speed...Should I think of force as the same as magnitude of the current velocity ? Thank you

[flcc]

Magnitude is just the length of the vector. The velocity is a vector that represent speed AND direction.
If you normalize it, you get just a direction.
If you calculate is length, you get the magnitude (or speed).

Velocity is just the result of all force applied to the object at time t. In real world you MUST apply force to make an object move.
In digital world you can effectively just set up the velocity. But as I wrote above, except for the initialization, that's not what you want to do.
What you want to do is modifying the velocity with forces (popwind, popforce etc...), or wrangle, or anything else.

But if in a wrangle for example, you write @v = @v * 0.01, you'll somehow have written a force (In this case a drag force).

[anim]

v@force and v@v in POPs are very close to force and velocity in physics, so if you read more about force and velocity in physics in general, you'll get better idea about what you are dealing with

there is many ways to describe them, so for example you can think of them like this

v@v is the current velocity per second, or in other words change of position per second

v@force is change of momentum per second, in simple case if @mass is 1 then v@force is the same as acceleration which is change of velocity per second, but more generally v@force describes change of velocity per second proportional to mass

 

so in other words, they are not the same, and in similar way to how velocity affects position, force affects velocity

Edited November 4, 2019 by anim

[logix1390]

@anim @flcc Thank you guys for the detailed descriptions. This makes a lot more sense to me.  Appreciate it !