Atruck horn emits a sound with a frequency of 238 hz. the truck is moving on a straight road with a constant speed. if a person standing on the side of the road hears the horn at a frequency of 220 hz, then what is the speed of the truck? use 340 m/s for the speed of the sound.

Uranium has two naturally occurring isotopes. 238u has a natural abundance of 99.3% and 235u has an abundance of 0.7%. it is the rarer 235u that is needed for nuclear reactors. the isotopes are separated by forming uranium hexafluoride uf6, which is a gas, then allowing it to diffuse through a series of porous membranes. 235uf6 has a slightly larger rms speed than 238uf6 and diffuses slightly faster. many repetitions of this procedure gradually separate the two isotopes. what is the ratio of the rms speed of 235uf6 to that of 238uf6? express your answer to five significant figures.