All Questions
72
questions
0
votes
3
answers
84
views
Conceptual meaning of frame of reference for kinetic energy
what does the statement
The speed, and thus the kinetic energy of a single object is frame-dependent (relative)
even mean? does the impact of a collision of moving bodies and henceforth transfer of ...
0
votes
2
answers
74
views
Accelerating body in a non-inertial frame of reference
If a body is subjected to a force, can I find a non-inertial frame of reference in which the body is not accelerating?
- 21
1
vote
1
answer
75
views
Principle of Relativity and the invariance of Newton's law in IRFs
Newton's law are form invariant under the coordinate substitutions:
$$
\tilde{x^{i}}=x^{i}+a^{i}
$$
This means that Newtons' equation of motion,
$$
F^{i}=m \frac{d^{2} x^{i}}{d t^{2}}
$$
(where $i=1,2,...
- 11
5
votes
2
answers
850
views
Does kinetic energy rely on the observer mass too since velocity is relative?
There is no 'correct' inertial reference frame according to relativity. Objects are only 'in motion' relative to an arbitrary inertial reference frame. So let us take the following example. A person ...
- 1,009
2
votes
1
answer
110
views
Flying mosquito problem [duplicate]
Let's say there is a car and its doors and windows are closed. Basically it is a closed space inside. There is a mosquito hovering right in the center of closed space of the car. While doing so the ...
- 39
1
vote
3
answers
9k
views
What exactly will happen if you jump in the upward direction from a roof of on a moving car?
I'm not a physicist and I'm a little bit puzzled with the image below:
I know it's a joke but if we assume we don't have air resistance what exactly will happen if someone jump in the upward ...
- 13
2
votes
5
answers
123
views
If motion relative to a frame of reference is purely relative, how do we account for the work done to move relative to the frame of reference?
I get the idea that everything is in motion, and there's no absolute reference frame for everything.
But when we consider local events, like a train passing through a town, I have trouble accepting ...
1
vote
0
answers
114
views
Work done on a moving cart in wind
Let us suppose a cart is moving in a rough ground with a propeller attached to the roof of the cart.
Let the velocity of the cart at the given point of analysis be V and velocity of wind is -W. The ...
3
votes
2
answers
67
views
Relative Velocity (Kinematics) [closed]
I was studying the concept of relative velocity and after solving a few problems I am running into this confusion.
a) Let’s say two cars are moving perpendicular to each other (no collision) with ...
- 31
5
votes
5
answers
1k
views
How should I understand the idea of relativity of space?
In the book General Physics by L.D.Landau, he mentioned the following in the first and second paragraph
The fundamental concept of mechanics is that of motion of a body with
respect to other bodies. ...
- 138
2
votes
1
answer
66
views
How would we know whether a object is moving in deep space?
In deep space, there isn't anything we can compare our position with (According to my knowledge). In other words, we won't be able to define an origin so how would we know whether we are in motion or ...
- 883
1
vote
2
answers
547
views
Coriolis force and liquid on a rotating space station?
On a rotating wheel space station crewed by humans with sea-level conditions (temperature above the freezing point), if liquid was spilled on the floor am I correct in understanding that the Coriolis ...
- 269
-1
votes
2
answers
91
views
Velocity Question from grandparent
My Grandparent asked me this question a few years ago, and I am getting around to giving him an answer, but I don't know the answer. Can anyone help?
"A pickup truck is speeding along a highway ...
- 21
0
votes
1
answer
312
views
Relative angular velocity of one point with respect to another on a solid rigid body [closed]
What is relative angular velocity of A wrt B and that of A wrt C in the figure given below?
Description:
A, B and C lie on a solid cylinder(rigid body) rotating with a constant angular velocity $\vec{...
- 147
0
votes
2
answers
286
views
Change in Kinetic Energy in two different reference frames (one of them non-inertial) [duplicate]
Let's say an object of mass 10 kg is fired from a cart of mass 90 kg. The object and the cart, of total mass 100 kg were initially moving together with a speed of 10 m/s. Then, the object is fired by ...
- 95