We all know that the Earth cycles through a regular pattern of days and nights.
What causes this pattern?

A) The tilt of the Earth on its axis.
B) The sun turns on, and then goes out.
C) The rotation of the Earth on its axis.
Eliminate
D) The rotation of the sun around the earth.

The passing of heat through a material while the material itself stays in place. a. radiation b. conduction c. convection

What are the necessary conditions for fusion?

In an old-fashioned amusement park ride, passengers stand inside a 3.0-m-tall, 5.0-m-diameter hollow steel cylinder with their backs against the wall. the cylinder begins to rotate about a vertical axis. then the floor on which the passengers are standing suddenly drops away! if all goes well, the passengers will “stick” to the wall and not slide. clothing has a static coefficient of friction against steel in the range 0.60 to 1.0 and a kinetic coefficient in the range 0.40 to 0.70. part a what is the minimum rotational frequency, in rpm, for which the ride is safe? express your answer using two significant figures. f f = rpm