A meteoroid, heading straight for Earth, has a speed of v = 11.5 km/s relative to the center of Earth as it crosses an orbit, a distance of r = 7.5×10^8 m from the earth's center. What is the meteroid's speed as it hits the earth? Neglect the effects of the moon, Earth's atmosphere, and any motion of the earth. (G = 6.67×10^−11 N • m2/kg2, M earth = 5.98×10^24 kg, R earth= 6.37×10^6 m.)

An asteroid is discovered in a nearly circular orbit around the sun, with an orbital radius that is 2.47 times earth's. what is the asteroid's orbital period, its "year," in terms of earth years?

Astudent is given an assignment to demonstrate diffraction. he takes a photograph of a straw in a glass of water. the straw appears bent at the water level. which best describes this example? a) this is a good example of diffraction. b) this is an example of dispersion and not diffraction. c) this is an example of refraction and not diffraction. d) this is an example of reflection and not diffraction.

The magnetic field inside a superconducting solenoid is 4.50 t. the solenoid has an inner diameter of 6.20 cm and a length of 26.0 cm. determine (a) the magnetic energy density in the field and (b) the energy stored in the magnetic field within the solenoid.