Discusses wave patterns on the surfaces of ripening wheat and barley crops when the wind is moderately strong. Examines the structure of the turbulence over such natural surfaces and conditions under which the crop may be damaged by the wind. (JR)

Consideration of the force of gravity in some simple accelerated systems. Ambiguity about the use of up'' and down'' arises in coordinate systems not at rest with respect to the surface of the earth. (DF)

A description of a field experience to demonstrate some basic principles concerning the geologic transport of beach sands. (Author/CP)

Presents a demonstration apparatus for Kepler's three laws of planetary motion consisting of an air-supported "satellite whose orbit on a level table surface is determined by an inverse square force generated by a Peaucellier linkage and long spring. The device can also be used to illustrate centrifugal force, statics, friction, momentum and…

The answers from test questions on circular motion are analyzed in terms of the misunderstandings of resultant force, kinematics, interaction, and centrifugal force. (DS)

The often observed and misunderstood phenomenon of movement of black and white vanes in toy radiometers under illumination is discussed in a generalized non-mathematical manner. Effects of light pressure, low gas density, friction, heat, and motion are illustrated. (JM)

Capillary and gravity water waves are related to the position, wavelength, and velocity of an object in flowing water. Water patterns are presented for ships and the whirling beetle with an explanation of how the design affects the objects velocity and the observed water wavelengths. (DS)