Which of the following must be true about an object for it to be in uniform circular motion? a. it must have zero centripetal acceleration. b, it must have increasing centripetal acceleration. c. it must be moving at a constant speed. d. it must be moving with a constant velocity.

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve

Which notation is used to represent an alpha particle? a. b. c. d.

What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 480 ? the index of refraction of the film is 1.34, and there is air on both sides of the film. express your answer in nanometers. hint 1. how to approach th