Mr. and mrs. tew attended this summer band concert to hear their son play his violin. they sat in the back row. they noticed that during the concert, the music seemed to changed in volume; sometimes it was very loud and other times they could barely hear it. they finally got up and moved to the fourth row, directly in front of the band. the problem seemed to lessen. what might have caused this change in volume during the band concert? a) constructive and destructive interference of sound waves. b) sound waves reflecting off of the ceiling, walls, and other hard surfaces. c) sound waves being absorbed by the walls and curtains in the concert hall. d) inconsistencies in the music play resulting in spotty sound wave production.

The energy of a photon was found to be 3.38 × 10–19 j. planck’s constant is 6.63 × 10–34 j • s. which color of light corresponds to this photon?

The softest and hardest minerals are: softest hardest

To understand the behavior of the electric field at the surface of a conductor, and its relationship to surface charge on the conductor. a conductor is placed in an external electrostatic field. the external field is uniform before the conductor is placed within it. the conductor is completely isolated from any source of current or charge. part a: which of the following describes the electric field inside this conductor? it is in the same direction as the original external field.it is in the opposite direction from that of the original external field.it has a direction determined entirely by the charge on its surface.it is always zero. part b: the charge density inside the conductor is: 0non-zero; but uniformnon-zero; non-uniforminfinite part c: assume that at some point just outside the surface of the conductor, the electric field has magnitude e and is directed toward the surface of the conductor. what is the charge density η on the surface of the conductor at that point? express your answer in terms of e and ϵ0