Sound with frequency 1300 Hz leaves a room through a doorway with a width of 1.14 m . At what minimum angle relative to the centerline perpendicular to the doorway will someone outside the room hear no sound? Use 344 m/s for the speed of sound in air and assume that the source and listener are both far enough from the doorway for Fraunhofer diffraction to apply. You can ignore effects of reflections.

If a refrigerator is a heat pump that follows the first law of thermodynamics, how much heat was removed from food inside of the refrigerator if it released 380j of energy to the room?

If you place a magnet under a clear dish, and sprinkle iron fillings over it, above what part of the magnet will most of the fillings gather

10 points! will mark brainiest! in a heat engine if 1,000 j of heat enters the system and the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2,000 j 1: write the equation2: list out your known variables 3: plug the numbers into the equations 4: solve 5: write your solution statement that includes initial energy and final energy added you so much!