- #1

LCSphysicist

- 646

- 162

- Homework Statement
- The hallmark of an inertial reference frame is that any object which is subject to zero net force will travel in a straight line at constant speed. To illustrate this, consider the following experiment: I am standing on the ground (which we shall take to be an inertial frame) beside a perfectly flat horizontal turntable, rotating with constant angular velocity ω. I lean over and shove a frictionless puck so that it slides across the turntable, straight through the center. The puck is subject to zero net force and, as seen from my inertial frame, travels in a straight line. Describe the puck's path as observed by someone sitting at rest on the turntable. This requires careful thought, but you should be able to get a qualitative picture. For a quantitative picture, it helps to use polar coordinates.

- Relevant Equations
- r = r*ur

v = r*ur + wru(theta)

Well, make the center of the polar coordinates at the center of the turntable, so put r along the ro initial.

I am well known that to someone who is rest on the turntable, the equations will be the follow:

dr/dt = ro - vt

If the turntable route with angular velocity w,

dtheta/dt = -wt

We could go on with this and finish the question.

But i want to know about the other way that i think to resolve the question starting by the velocities:

We will have v = v = r*ur + wr*u(theta)

v = -v*ur - w(ro-vt)u(theta)

I don't know how should i proceed here..

I am well known that to someone who is rest on the turntable, the equations will be the follow:

dr/dt = ro - vt

If the turntable route with angular velocity w,

dtheta/dt = -wt

We could go on with this and finish the question.

But i want to know about the other way that i think to resolve the question starting by the velocities:

We will have v = v = r*ur + wr*u(theta)

v = -v*ur - w(ro-vt)u(theta)

I don't know how should i proceed here..