- #1
abertram28
- 54
- 0
Im doing a problem with variable frictional forces.
My main equation is -mkv^2=F . We are to assume the force driving the object remains constant, kinda like a boat on the lake full bore.
So, I set my F=ma equation up.
-mkv^2=m(dv/dt)
Next I removed m and inverted both equations to solve for dt.
-dv/(kv^2)=dt
Next I intetegrated both sides seperately. I was taught to use a "dummy variable" by marking v and t somehow. I simply chose to use a superscript prime marking on my paper. anyhow... Ill use a little v for real velocity and big V for dummy velocity.
(1/kV)|0 to v = t
Isnt that (1/kv) - (1/0) ?
This equation doesn't solve nicely. In my setup I am given the equation for velocity and only asked to show how I got it.
V=Vo / (1 + Vo*kt)
Please help... I posted part of this problem over in classical when I had a different problem with it, so please don't flame me for double posting or spamming the board. If that's your opinion I couldn't care less.
TIA to anyone who helps!
My main equation is -mkv^2=F . We are to assume the force driving the object remains constant, kinda like a boat on the lake full bore.
So, I set my F=ma equation up.
-mkv^2=m(dv/dt)
Next I removed m and inverted both equations to solve for dt.
-dv/(kv^2)=dt
Next I intetegrated both sides seperately. I was taught to use a "dummy variable" by marking v and t somehow. I simply chose to use a superscript prime marking on my paper. anyhow... Ill use a little v for real velocity and big V for dummy velocity.
(1/kV)|0 to v = t
Isnt that (1/kv) - (1/0) ?
This equation doesn't solve nicely. In my setup I am given the equation for velocity and only asked to show how I got it.
V=Vo / (1 + Vo*kt)
Please help... I posted part of this problem over in classical when I had a different problem with it, so please don't flame me for double posting or spamming the board. If that's your opinion I couldn't care less.
TIA to anyone who helps!