# Questions tagged [momentum]

In introductory mechanics, the momentum of a particle is its mass times its velocity. In electrodynamics, the momentum of a field is proportional to the cross-product of the electric field with the magnetic field. In special relativity, momentum is generalized to four-momentum.

3,122 questions
Filter by
Sorted by
Tagged with
6 views

### Force of brake pads on a wheel

I have a hollow-cylinder wheel model, braked with brake pads located at a distance d of the wheel's center axis. The brake pads have a contact area S. They are also forced towards the wheel with a ...
16 views

### Cosmic strings and conservation of momentum

I've been told that cosmic strings useful don't give of gravity. I've been told that if an objects passive and active gravitational masses differ then this will result in a violation of conservation ...
11 views

### Experiment of liquid filled rod doing oscillation is called?

I know this is a weird question but I can't find any reference to this experiment, I have Google a lot and now I need the experts help. There is a physics experiment where a liquid filled rod is ...
14 views

### MOMENTUM With Compressed massless Spring [closed]

How did they arrive at the answer (b)
88 views
+50

### Linear Momentum in General Relativity

My question is, does a particle moving in a straight line at constant velocity through empty space create "frame dragging" that would tend to entrain other bodies in the direction of its ...
56 views

### Angle-free two-dimensional inelastic collision formula?

I'm trying to calculate velocities (by components - x, y) of two objects (balls) after inelastic, two-dimensional collision. I've successfully implemented the angle-free formula for elastic two-...
72 views

### Can you explain me the definition of wave number as defined in theoretical physics?

Wavenumber, as used in spectroscopy and most chemistry fields, is defined as the number of wavelengths per unit distance. The corresponding formula is $$k=\frac{1}{\lambda}.$$ However, in theoretical ...
94 views

102 views

### Is light's momentum $0$?

From Paul Dirac's extended mass-energy equivalence equation, we know that, E2 = (mc2)2 + (pc)2 We also know that E = mc2 So, if we write mc instead of ...
52 views

### Do you have to leave something behind to go forward? (ie a contained system)

By "behind" I mean a particle outside of the box. ( assume a 1d system)Imagine a closed box. And at the very center of that box, is a device that fires particles 1,2 in opposite direction. ...
420 views

### Is it possible to move without throwing or pushing another object or energy?

All kinds of movement occur when a thing throws something out or pushes something back and then the thing moves. Like the car pushes the road back, the rockets throw gases at high speed to move. ...
68 views

### Can we convert momentum to coulombs in any simple sense?

Let's suppose hypothetically you throw a specially shaped magnet designed with sliding plates, and when it hits the ground it converts almost all it's momentum, or if need be for more complications, ...
21 views

### Motion and momentum of spinning mass

Two college friends get together 50+ years after their physics class and begin to discuss forces, momentum, spinning bodies, and space propulsion. It developed that they had widely differing opinions ...
28 views

### Superposition of momentum plane waves for a WF: discrete of continuous?

On the one hand there is a theorem that states that any reasonable wave function $\Psi$ can be written as a superposition of eigenstates of $\hat Q$ (a hermitian operator). So if $\Psi _i$ are the ...
53 views

54 views

### Velocity of a boat after getting off of it

A 50 kg person gets off of a 100 kg boat at rest with a velocity of 10 m/s. What will be the velocity of the boat in the opposite direction? Apparently, the momentum of the person and the boat are ...