So be it. If I use F = qE, and acceleration a = F/m, I get 8:1 since the velocities are proportional to a^2. But if we had to take the inter-particular forces into consideration, I couldn't use that formula, since the repulsive force would vary with intervening distance.
I'm afraid I'm not getting it. Conservation of momentum gives 2:1, and for conserving energy, I don't know the distance between the charges to calculate potential energy.
Homework Statement
Two charges of masses m and 2m, charges 2q and q respectively are placed in a uniform electric field and are allowed to move at exactly the same time. Find the ratio of their kinetic energies.
Homework Equations
Field = qE
Force =(Kq1q2)/r^2
Kinetic energy=1/2mv^2...
The MI's are correct, and yes, they are all of same mass and radius. One question: can we find the acceleration of c.o.m and then use the equations of motion to find final velocity? I haven't tried that.
Homework Statement
Find the ratio of the translational kinetic energies of a ring, a coin, and a solid sphere at the bottom of an inclined plane. The bodies have been released from rest at the top. Assume pure rolling without any slipping.
The Attempt at a Solution
Well, I'm really not...
I'm assuming that was rhetorical. :P
I think you should just find the resultant of the momentum vectors, and then arctan[(y-component)/(x-component)] (components of resultant) should give you the angle.
Well, the work done by the force is equal to (-k*x^2)/2, where x is the max. deformation of the spring. This can be found by integration. But I'm not sure how the setup looks and how you're applying the force.