A person standing a certain distance from an airplane with four equally noisy jet engines is experiencing a sound level of 143 dB . Part A What sound level would this person experience if the captain shut down all but one engine? [Hint: Add intensities, not dB's.]

Calculate the kinetic energy of earth due to its spinning about its axis. krot = j compare your answer with the kinetic energy of the orbital motion of earth's center of mass about the sun. assume earth to be a homogeneous sphere of mass 6.00 1024 kg and radius 6.40 106 m. the radius of earth's orbit is 1.50 1011 m.

What property is a characteristic of a substance that can be observed and does not change the identity of the substance

The magnitude of the poynting vector of a planar electromagnetic wave has an average value of 0.939 w/m^2 . the wave is incident upon a rectangular area, 1.5 m by 2.0 m, at right angles. how much total electromagnetic energy falls on the area during 1.0 minute?