The speed at which any planet moves through space is constantly changing. in a perfectly circular orbit, the orbital radius of the planet would be constant and therefore so would be its observed angular velocity. in elliptical orbits, the angular velocity varies. in elliptical orbits, the orbital radius of the satellite will vary and therefore so will its angular velocity. the planet travels "faster" (greater angular velocity) when closer to the sun, then "slower" (less angular velocity) at a more distant radius. according to newton's 2nd law, what is the underlying force behind this change in velocity? a) mass b) gravity c) friction d) projectile motion

The earth's moon is unusually large. two popular theories of the moon's origin include the "sister world" hypothesis, which states that the moon formed from the same materials as the earth, near enough to the earth that they fell into orbit around each other. a second theory is the "capture" hypothesis, in which the moon formed elsewhere in the solar system, and the earth's gravity pulled it into its orbit. studies of what the moon is made of indicate that some of its materials had to come from the earth or from the same area of the solar system where the earth had formed. at the same time, the moon does not contain much of the material that makes up the earth's core, so the moon could not have formed from the same materials as the earth. how do the two facts above affect the described theories of the moon's origin? a. they show that scientists will never agree on where the moon came from. b. they show that more experiments on moon formation need to be done. c. they show that no theory accounts for the existence of the moon. d. they show that neither theory is complete and entirely correct.

What is the main reason why some developing countries fear the increase the free trade policies around the world?

Which of the following is true about a carbonated soft drink? . the carbon dioxide is the solvent, and water is the solute.. the water is the solution, and carbon dioxide is the solvent.. the carbon dioxide is the solution, and the water is the solvent.. the water is the solvent, and the carbon dioxide is the solute.. .