General Circulation Models (GCM) : a) use data collected exclusively from high-resolution satellites.
b) use spectral models derived from energy released from the earth and clouds.
c) can be run on powerful home computers, allowing citizen scientists to run models.
d) use complicated two-dimensional grid systems that change temporally.

Certain bacteria (such as aquaspirillum magnetotacticum) tend to swim toward the earth’s geographic north pole because they contain tiny particles, called magnetosomes, that are sensitive to a magnetic field. if a transmission line carrying 100 a is laid underwater, at what range of distances would the magnetic field from this line be great enough to interfere with the migration of these bacteria? (assume that a field less than 5% of the earth’s field would have little effect on the bacteria. take the earth’s field to be 5.0 * 10-5 t, and ignore the effects of the seawater.)

Which of the following is a true statement about the acceleration ~a of the pendulum bob ~a is equal to the acceleration due to gravity. ~a is perpendicular to the bob’s trajectory. ~a is equal to the instantaneous rate of change in velocity. ~a is tangent to the bob’s trajectory.

Find an expression for the electric field e⃗ at the center of the semicircle. hint: a small piece of arc length δs spans a small angle δθ=δs /r, where r is the radius. express your answer in terms of the variables q, l, unit vectors i^, j^, and appropriate constants.