At a rock concert, a dB meter registered 135 dB when placed 2.2 m in front of a loudspeaker on the stage.

1) What was the power output of the speaker, assuming uniform spherical spreading of the sound and neglecting absorption in the air?
2) How far away would the sound level be a somewhat reasonable 95 dB?

Consider the growth of a 20-nm-diameter silicon nanowire onto a silicon wafer. the temperature of the wafer surface is maintained at 2400 k. assume the thermal conductivity of the silicon nanowire is 20 wm-1k-1 and all its surfaces including the tip are subjected to convection heat transfer with the coefficient h = 1×105 wm-2k-1 and t∞ = 8000 k. when the nanowire grows to l = 300 nm, what is the temperature of the nanowire tip (t (x =

Which best describes the difference between internal and thermal energy?

Use the drop-down menus to answer each question. which line represents the movement of a cart with a constant acceleration? a which line represents the movement of a cart with a constant velocity? c which lines represents a cart with no velocity or acceleration? b