Help !! You are using sonar over a spot in the ocean known to be 91.8 m deep. The system emits a 50.0-kHz pulse into the water. It takes 120.0 ms for the sound to travel to the ocean floor and back to the sonar system. Determine the speed of sound in the ocean and the wavelength of the sonar pulse.

Tungsten-filament lightbulb emits light based on the temperature of the filament. which phenomenon does this demonstrate?

Comedians like to joke that the reason we haven’t been visited by intelligent life from elsewhere in the universe is that aliens have been monitoring earth’s broadcasts of intellectually embarrassing tv programs, like gilligan’s island, fear factor, the jersey shore, and the jerry springer showand so consider us far too primitive to merit a visit. let’s check the assertion that aliens could have been receiving them. tv programs are broadcast at a frequency of about 100mhz with about 100kw of total power in 30frames per second, which emanatesroughly uniformly in all directions. assume that interstellar space transmits these broadcasts without attenuation. no matter how smart they are, aliens would require at least one photon per frame to interpret our signals. findthe number of photons per unit time per unit area reaching a receiver on a possible planet in the nearest star system, which is about 4 light-years away (a light-year is the distance light travels in a year). if aliens aimed a receiver or detector directly at earth, how big (in diameter) would it have to be to receive a photon per frame

Acid precipitation chemically weathering a 5.0-kg limestone rock . which coukd be the result ?