Which of the following is not a characteristic of a sound wave?

a) it is longitudinal
b) it transfers energy by moving the medium perpedicular to the motion of the wave
c) it transfers energy by moving the medium parallel to the motion of the wave
d) it is a mechanical wave

Amichelson interferometer operating at a 600 nm wavelength has a 3.02-cm-long glass cell in one arm. to begin, the air is pumped out of the cell and mirror m2 is adjusted to produce a bright spot at the center of the interference pattern. then a valve is opened and air is slowly admitted into the cell. the index of refraction of air at 1.00 atm pressure is 1.00028.how many bright-dark-bright fringe shifts are observed as the cell fills with air?

In which of the following is positive work done by a person on a suitcase

Scientists follow specific processes in order to determine valid explanations and conclusions from observations. david observed strange lights in the sky above his home outside of roswell, new mexico. the only explanation that makes sense to him is that there are ufos in the area. what should david do next to verify his explanation?