Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Curvilinear Motion: Polar Coordinates

Curvilinear Motion: Polar Coordinates

In polar coordinates, the motion of a particle follows a curvilinear path. The radial coordinate symbolized as 'r,' extends outward from a fixed origin to the particle, while the angular coordinate, 'θ,' measured in radians, represents the counterclockwise angle between a fixed reference line and the radial line connecting the origin to the particle.
The particle's location is described using a unit vector along the radial direction. Deriving the particle's position...

Equations of Motion: Normal and Tangetial Components

Equations of Motion: Normal and Tangetial Components

Describing the motion of a particle along a curvilinear path involves understanding its components in terms of normal and tangential aspects. The normal component aligns with the radial direction of the curve at a specific point, reflecting changes in the trajectory of the velocity vector. In contrast, the tangential component is tangential to the curve at that point and signifies the rate at which speed alters along the path.
Newton's second law of motion is employed to articulate the...

Velocity Potential

Velocity Potential

In steady, incompressible flow through a long, straight pipe with a uniform cross-section, the flow in the central region (far from the pipe walls) is irrotational. This irrotational nature means that fluid particles do not rotate around their axes, and a scalar function called the velocity potential, represented by ϕ, can be used to describe their movement. In irrotational flows, the velocity field V is defined as the gradient of the velocity potential:

Relating Angular And Linear Quantities - II

Relating Angular And Linear Quantities - II

In the case of circular motion, the linear tangential speed of a particle at a radius from the axis of rotation is related to the angular velocity by the relation:

Momentum And Radiation Pressure

Momentum And Radiation Pressure

An object absorbing an electromagnetic wave would experience a force in the direction of propagation of the wave. This force occurs because electromagnetic waves contain and transport momentum. The force accounts for the wave's radiation pressure exerted on the object. Maxwell's prediction was confirmed in 1903 by Nichols and Hull by precisely measuring radiation pressures with a torsion balance. The measuring instrument had mirrors suspended from a fiber kept inside a glass container.

Non-uniform Circular Motion

Non-uniform Circular Motion

In uniform circular motion, the particle executing circular motion has a constant speed, and the circle is at a fixed radius. However, not all circular motion occurs at a constant speed. A particle can travel in a circle and speed up or slow down, showing an acceleration in the direction of motion. In that case, the motion is called non-uniform circular motion, and an additional acceleration is introduced, which is in the direction tangential to the circle.
For example, such...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Frozen-In Gravitational Fields.

Physical review letters·2026

Same author

Radiative Particle-in-Cell Simulations of Turbulent Comptonization in Magnetized Black-Hole Coronae.

Physical review letters·2024

Same author

Generation of Near-Equipartition Magnetic Fields in Turbulent Collisionless Plasmas.

Physical review letters·2023

Same author

Reconnection-driven energy cascade in magnetohydrodynamic turbulence.

Science advances·2022

Same author

Relativistic Asymmetric Magnetic Reconnection.

Physical review letters·2022

Same author

Nonideal Fields Solve the Injection Problem in Relativistic Reconnection.

Physical review letters·2022

Search research articles

Related Experiment Video

Updated: Oct 6, 2025

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

Published on: June 24, 2016

Pitch-Angle Anisotropy Controls Particle Acceleration and Cooling in Radiative Relativistic Plasma Turbulence.

Luca Comisso¹, Lorenzo Sironi¹

¹Department of Astronomy and Columbia Astrophysics Laboratory, Columbia University, New York, New York 10027, USA.

Physical Review Letters

|January 14, 2022

Summary

High-energy astrophysical sources accelerate particles efficiently, even with strong radiation losses. Simulations reveal magnetically dominated turbulence creates nonthermal particle spectra, explaining extreme cosmic emissions.

More Related Videos

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

Published on: February 27, 2016

Uncoupling Coriolis Force and Rotating Buoyancy Effects on Full-Field Heat Transfer Properties of a Rotating Channel

Uncoupling Coriolis Force and Rotating Buoyancy Effects on Full-Field Heat Transfer Properties of a Rotating Channel

Published on: October 5, 2018

Related Experiment Videos

Last Updated: Oct 6, 2025

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

Published on: June 24, 2016

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

Published on: February 27, 2016

Uncoupling Coriolis Force and Rotating Buoyancy Effects on Full-Field Heat Transfer Properties of a Rotating Channel

Uncoupling Coriolis Force and Rotating Buoyancy Effects on Full-Field Heat Transfer Properties of a Rotating Channel

Published on: October 5, 2018

Area of Science:

Astrophysics
Plasma Physics
High-Energy Physics

Background:

Nature's most powerful high-energy sources accelerate particles to high energies and radiate them away on extremely short timescales.
The physical processes enabling efficient particle acceleration despite significant radiative losses remain unclear.

Purpose of the Study:

To investigate the physical mechanisms behind efficient particle acceleration in high-energy astrophysical sources.
To understand the generation of nonthermal particle spectra and their radiative signatures.

Main Methods:

Radiative particle-in-cell simulations were employed.
The simulations focused on magnetically dominated turbulence in pair plasmas with strong synchrotron cooling.

Main Results:

A nonthermal particle spectrum with a hard power-law (slope p~1) was generated within a few eddy turnover times.
Low pitch-angle particles exceeded radiation-reaction limits before cooling; the spectrum hardened over time (p<1).
The resulting synchrotron spectrum was hard (νF_{ν}∝ν^{s} with s~1).

Conclusions:

Magnetically dominated turbulence with strong synchrotron cooling can produce efficient particle acceleration and nonthermal spectra.
These findings explain the observed emission from high-energy astrophysical sources like gamma-ray bursts and Crab nebula flares.