Related Experiment Video
Updated: Feb 8, 2026

Measuring Microbial Mutation Rates with the Fluctuation Assay
Published on: November 28, 2019
Dependence of Perpendicular Viscosity on Magnetic Fluctuations in a Stochastic Topology
R Fridström1, B E Chapman2, A F Almagri2
1Department of Fusion Plasma Physics, School of Electrical Engineering, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden.
Abstract:
In a magnetically confined plasma with a stochastic magnetic field, the dependence of the perpendicular viscosity on the magnetic fluctuation amplitude is measured for the first time. With a controlled, ∼ tenfold variation in the fluctuation amplitude, the viscosity increases ∼100-fold, exhibiting the same fluctuation-amplitude-squared dependence as the predicted rate of stochastic field line diffusion. The absolute value of the viscosity is well predicted by a model based on momentum transport in a stochastic field, the first in-depth test of this model.
Related Concept Videos
Viscosity
The SI unit of viscosity is...
Surface Tension, Capillary Action, and Viscosity
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
Perpendicular-Axis Theorem
Consider a circular disc of mass M and radius R lying along an x-y plane. The origin lies at the center of the disc, and the z-axis is perpendicular to the disc's plane. All three axes coincide at the disc's center. The moment of inertia of this...
Viscosity of Fluid
Frequency-dependent Selection
Drug Dependence

