Which of the following correctly describes the conditions under which you will feel weightless, according to general relativity? a. any time you are traveling through space at constant speed
b. any time your worldline is perfectly straight
c. any time your worldline is following the straightest possible path through spacetime
d. any time you are very far from any planet
e. You can never be truly weightless.

Ultraviolet radiation is dangerous because it has a high enough energy to damage skin cells. what is the best explanation of the relationship between wavelength and wave energy? a) wave energy is related only to frequency, not wavelength. b) longer wavelengths have lower frequencies but higher energy. c) the shorter the wavelength, the lower the frequency and the higher the energy. d) the shorter the wavelength, the higher the frequency and the higher the energy.