I don't know when to use the kinetic or when to use the rotational kinetic and since I don't have the mass of the ball here I guess it will be the rotational kinetic they are asking for, but I don't want to guess in further problems. What logic to use to know which one they are asking for?
a) velocity=(2*Pi*(1.5*10^11m))/(365days*24*60*60) why the 2pi? Can't I just calculated without the 2*pi, I mean isn't velocity = distance / time?
b) I = 2/5 MR^2 = 2/5 ((6.0*10^24kg)(6.4*10^6m)^2)
w = (2pi)/(24h*60min*60s) = 6.2831 / 86400s = 7.27 * 10^-5 rad/s and
then I plug them in...
A marble of mass M and radius R rolls without slipping down the track on the left from a height h1. The marble then goes up the frictionless track on the right to a height h2 where h2<h1 . Find h2.
I don't know how to think of this one, any hints please?
A billiard ball initially at rest is given a sharp blow by a cue stick. The force is horizontal and is applied at a distance 2R/3 below the centreline of the ball. The initial speed of the ball is v0 and the coefficient of kinetic friction is Mu k. a) what is the initial angular speed w0? B)...
Calculate the kinetic energy of rotation of the Earth about its axis, and compare it with the kinetic energy of the orbital motion of the earth’s centre of mass about the sun. Assume the Earth to be a homogeneous sphere of mass 6.0*10^24kg and radius 6.4*10^6m. The radius of the earth’s orbit is...
you mean
L = m * 800m/s * 3m
and L = I*w= 4000kg.m^2 * 0.6286 rad/sec = 2513.27 kgm^2/s
so 2513.27 = m * 800m/s * 3m
and m = 2513.27 /(800m/s*3m)= 2513.27 / 2400 = 1.04 kg (I.m not sure of the rounding again)
t = 1.04kg/0.01kg/s = 104s ?