- #1
Dragster
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I really do not see how I can solve the problems. All I need is hint how to start the problems most of the time. I know I should read more, ask questions to teacher, etc. I have 5 classes, 5 homeworks to do every week. On top of that I have to revise old courses, remember the old stuff I used to know and study for the courses of the following week. It is really hard with my schedule to see the demonstrators or the teachers.
Add to that I am not an english native speaker and my teacher gave us an english book despite the course being in french and our first physics course.
I am not asking you to do the problems, just give me some hint where I should start and what I should use.
f lin (linear) or f quad (quadratic) being the drag force
For 2.2 (2.3) is flin = bv (2.5) value is equal to 1.6E-4 N*s/m^2
β=3πη which gives me the equation flin= 3πηDv = βDv = bv
2.4 What is cross-sectional area A? fquad= cv^2 c=γD^2 where γ= 0.25N*s^2/m^4
I guess that ∂Av^2 is actually cv^2 where c=∂A in this medium but I don't know how to prove the projectile encounters the fluid at the rate of ∂Av and all the more so ∂Av^2
2.11 m dy/dt = -mg -bv
a)
vy= -gt -bvt/m +v0 (1st integration gives the speed)
y= -gt^2 -bvt^2/m +v0t (2nd integration) gives the position
b) When v0= 0 we have ymax
y= -gt^2 -bvt^2/m +v0t
ymax= -gtmax^2 -bvtmax^2/m
tmax^2= ymax/(-(gm+bv)/2m)
c) no idea...
2.12 Again no idea how to begin this
2.13 With 2.12 solved I should be able to do it.
+karma for any help
I really do not see how I can solve the problems. All I need is hint how to start the problems most of the time. I know I should read more, ask questions to teacher, etc. I have 5 classes, 5 homeworks to do every week. On top of that I have to revise old courses, remember the old stuff I used to know and study for the courses of the following week. It is really hard with my schedule to see the demonstrators or the teachers.
Add to that I am not an english native speaker and my teacher gave us an english book despite the course being in french and our first physics course.
I am not asking you to do the problems, just give me some hint where I should start and what I should use.
f lin (linear) or f quad (quadratic) being the drag force
For 2.2 (2.3) is flin = bv (2.5) value is equal to 1.6E-4 N*s/m^2
β=3πη which gives me the equation flin= 3πηDv = βDv = bv
2.4 What is cross-sectional area A? fquad= cv^2 c=γD^2 where γ= 0.25N*s^2/m^4
I guess that ∂Av^2 is actually cv^2 where c=∂A in this medium but I don't know how to prove the projectile encounters the fluid at the rate of ∂Av and all the more so ∂Av^2
2.11 m dy/dt = -mg -bv
a)
vy= -gt -bvt/m +v0 (1st integration gives the speed)
y= -gt^2 -bvt^2/m +v0t (2nd integration) gives the position
b) When v0= 0 we have ymax
y= -gt^2 -bvt^2/m +v0t
ymax= -gtmax^2 -bvtmax^2/m
tmax^2= ymax/(-(gm+bv)/2m)
c) no idea...
2.12 Again no idea how to begin this
2.13 With 2.12 solved I should be able to do it.
+karma for any help
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