Physics - Browse Physics

81.

Focus

Softening the Blow

Phys. Rev. Focus 15, 9 (2005) – Published March 17, 2005

A specially designed layer of granular material can provide improved protection against sudden impacts, a theorist predicts.

82.

Focus

Motoring Oil Drops

Phys. Rev. Focus 15, 7 (2005) – Published February 22, 2005

Oil droplets zip around the bottom of a petri dish powered by their attraction to surfactant molecules and can cover the same ground many times.

83.

Focus

A Soapy Solution

Phys. Rev. Focus 14, 22 (2004) – Published December 1, 2004

Colorful soap films confirm an old theory on mixing in a turbulent fluid.

84.

Focus

When Membranes Collide

Phys. Rev. Focus 14, 20 (2004) – Published November 16, 2004

Researchers have measured the energy required for two membranes to fuse–the process that occurs when a virus attacks a cell.

85.

Focus

Getting an Extra Bounce

Phys. Rev. Focus 14, 14 (2004) – Published October 4, 2004

Computer simulations and experiments show that a ball can rebound from a surface with more vertical speed than it had initially.

86.

Focus

A New Direction for Liquid Crystals

Phys. Rev. Focus 13, 16 (2004) – Published April 12, 2004

After decades of searching, researchers identified a new type of liquid crystal where the molecules align in two dimensions, rather than one.

87.

Focus

Breaking Up Isn’t Hard To Do

Phys. Rev. Focus 13, 4 (2004) – Published January 30, 2004

Forcing water drops through a T-shaped intersection of tubes breaks them into droplets of reproducible size.

88.

Focus

Craters in a Sandbox

Phys. Rev. Focus 12, 8 (2003) – Published September 12, 2003

Researchers study lunar crater formation by dropping balls into sand.

89.

Focus

Mixing it Up (Or Not)

Phys. Rev. Focus 11, 20 (2003) – Published May 8, 2003

Water can play a dual role in granular mixtures, encouraging mixing in some situations but discouraging it in others.

90.

Focus

New Wrinkle On Fighting Crow’s Feet

Phys. Rev. Focus 11, 7 (2003) – Published February 20, 2003

A new theory predicts the structure of wrinkles in thin sheets of any material and may offer ways of eliminating them.

91.

Focus

Underwater Desert

Phys. Rev. Focus 10, 25 (2002) – Published December 10, 2002

A new technique generates miniature dunes in a water tank and appears to verify fundamental principles of dune formation.

92.

Focus

Scaling the Crumpled Heights

Phys. Rev. Focus 9, 7 (2002) – Published February 1, 2002

Experiments on the response of crumpled sheets to a squeezing force help explain their extraordinary strength.

93.

Focus

Swirling Sand Mimics Liquid and Gas

Phys. Rev. Focus 7, 31 (2001) – Published June 29, 2001

Sand flowing down a rough slope forms eddies–the first example of spontaneous vortices in a granular material.

94.

Focus

Elastomers Make Light Work

Phys. Rev. Focus 7, 32 (2001) – Published June 29, 2001

A new material stretches and contracts in response to light.

95.

Focus

Foamy Flows

Phys. Rev. Focus 7, 22 (2001) – Published May 14, 2001

A comparison of foams made with two different gases supports a theory on how foam changes over time.

96.

Focus

Flexibility of Cell Membranes

Phys. Rev. Focus 7, 9 (2001) – Published February 23, 2001

A new technique measures the mechanical properties of cell membranes by watching the motion of small beads attached to 20-micrometer-diameter bubbles of membrane surrounded by a layer of protein.

97.

Focus

Anatomy of a Jam

Phys. Rev. Focus 6, 29 (2000) – Published December 27, 2000

In the first quantitative study of the jamming of grain hoppers, a team derived a mathematical model that could lead to improved hopper designs.

98.

Focus

Why Like Charges Attract

Phys. Rev. Focus 6, 25 (2000) – Published December 6, 2000

Two negatively charged beads near a wall in water can attract one another. This surprising result may in some cases be explained by the fluid flow created as they are repelled by the wall.

99.

Focus

Toothpaste Is a Glass

Phys. Rev. Focus 6, 24 (2000) – Published November 28, 2000

The puzzling properties of toothpaste-like materials make sense, based on new experiments showing that pastes have much in common with glasses–disordered materials that physicists have been studying for many years.

100.

Focus

An Ideal Gas of Beads

Phys. Rev. Focus 6, 16 (2000) – Published October 10, 2000

A set of violently shaken beads exhibits a velocity distribution similar to that of an ideal gas, regardless of the shaking speed, suggesting that a fundamental theory of granular materials may be possible.