)the rectangular steel plate below measures 1 m x 0.5 m x 10 mm. assume that the 1 m dimension is in the x-direction and the 0.5 m dimension is in the y-direction. the plate is made of a material with an elastic modulus of 200 gpa and poisson’s ratio of 0.3. suppose a uniform normal stress, σx, of 125 mpa is applied in the x-direction. a) calculate the stress, σy, required to produce a transverse strain εy = 0 (in mpa). b) compute the normal strains in the x- and z-directions. [ans. to check εx = 0.000569] c) calculate the change in volume the plate will experience in mm3 .

there are no atoms

the aurora is formed when charged particles emitted from the sun during a solar flare penetrate the earth's magnetic shield and collide with atoms and molecules in our atmosphere. these collisions result in countless little bursts of light, called photons, which make up the aurora.

auroras are generated by charged solar particles hitting molecules in earth's atmosphere. this usually happens in high latitudes, because our planet’s magnetic field tends to funnel these particles toward the poles. that’s why it can be experienced in northern ohio.

365.25 earth days are in the year of a light year