Homework Statement
A charged particle of mass m and charge q is free to move in the horizontal (x, y) plane, under
the influence of the Coulomb potential due to another charge Q that is fixed at the origin.
Find the Lagrangian and the differential equations of motion of the mass m, in...
ok tiny-tim i think i got it, tell me if I am right.
Fnet = F1 - Fg
Moment about End
\sum=N - (l/2)Fg=0
0=Iw' - (l/2)(mg)
0=(ml^2/12)w' - (l/2)(mg)
w'= 6g/l
Moment about center of mass
\sum= N*(l/2)
=Iw' * (l/2)
=(ml^2/12)(6g/l)*(l/2)
=(1/4)mg
hey tiny-tim i have taken the moment about the centre:
\sum\tau=0=ml^2/12*w'-mg*l/2
w'=(gl/2)*(12/l^2)
=(g6)/l
I am now confused what to do next, you said to take moments about the centre. Is it just :
\sum\tau=0=ml^2/12*w' ?
Thanks
After the person has dropped the plank, the force becomes a torque.
Fnet = N - mg = ma
ma = (ml^2)/12 * w' - mg [(ml^2)/2 - for a thin uniform plank]
I am now stuck on what to do with w'.
Homework Statement
Two People are holding the ends of a uniform plank of lenth, l and mass, m. Show that if one person suddenly let's go, the load suppored by the other person suddenly drops from mg/2 to mg/4.
Homework Equations
Fnet=ma
L=Iw'
I=ml^2+I'
The Attempt at a Solution...
Homework Statement
Average Wind Velocity 38km/h [25 degrees N of E]
Helicopter needs to achieve 91km/h [17 degrees W of N]
Homework Equations
r=sqrt(x^2+y^2)
The Attempt at a Solution
y=38sin25 + 91sin98 = 106.17
x=38cos25 - 91cos98 = 47.1
r= 116.15
answer should be 94km/h