All Questions
10
questions
0
votes
2
answers
74
views
Energy in different coordinates in central force motion
With reference to central force, we see that K.E has 2 terms in 2D cartesian cordinate but just 1 term in polar coordinates and potential energy has 1 term in cartesian but 2 terms in polar.
Basically ...
- 367
4
votes
1
answer
61
views
Moving body is collided with a spring system.Why there is a difference in maximum compressed distance for different observers?
Suppose a body of mass m moving with velocity collides with a spring system.The event is being observed by two observers, one at rest and one moving with a velocity v opposite direction to that of the ...
- 538
2
votes
1
answer
170
views
Why is this hamiltonian not the energy? [duplicate]
Let a pendulum of length $\ell$ be connected to a rod that rotates with constant angular velocity $\omega$. $\theta$ is the angle of the pendulum wrt $z$ axis ($z$ axis is parallel to the rod).
I ...
- 980
3
votes
1
answer
1k
views
Why is total kinetic energy always equal to the sum of rotational and translational kinetic energies?
My derivation is as follows.
The total KE, $T_r$ for a rigid object purely rotating about an axis with angular velocity $\bf{ω}$ and with the $i$th particle rotating with velocity $ \textbf{v}_{(rot)...
user86425
-1
votes
1
answer
34
views
Kinetic energy problem for only one existing object
If only a single object were to exist in the universe, what would be the measure of its kinetic energy?I mean what would determine the velocity of the object?I could be one,or could be hunder thousand ...
- 164
1
vote
1
answer
605
views
Kinetic Energy in Newtonian Mechanics vs General Relativity?
In Newtonian mechanics, the kinetic Energy is a form of energy given by $\frac{1}{2}mv^2$.
Since Newtonian Mechanics is a limiting case of the more general General Relativity (when the curvature of ...
- 223
3
votes
1
answer
135
views
change of energy in changing frame of reference
Let's imagine a car that can jump onto, or off a moving train. The train moves at 10m/s. The car, on a road next to the train, accelerates to the same 10m/s, jumps off a ramp and lands on the train, ...
- 2,988
4
votes
2
answers
598
views
Work done changes between reference frames?
(This is not homework; a friend shared with me this puzzler and neither of us can figure it out.) Suppose you are in a plane traveling at velocity $v_1$ relative to the ground. The flight attendent ...
- 43
6
votes
1
answer
603
views
Energy usage in different reference frames
Imagine a moving object at constant speed (like a car). This object is, then, accelerated for a brief moment. In different reference frames (at rest and moving along with the object), the variation of ...
- 133
1
vote
1
answer
166
views
kinetic energy of the stone
Suppose we have a man traveling in an open car (roof open) with speed $v$ towards right (man faces right). He throws a stone (mass $m$) towards right, in his frame-forward with speed $V$.
In the ...
- 824