Imagine that you are located on earth while a spaceship travels from earth to the star vega at constant velocity of 0.8c. the following items describe quantities that, according to einstein’s special theory of relativity, would be either larger (or longer), smaller (or shorter), or the same as their rest values. (note that by "rest value," we mean the value you would find if both you and the spaceship were at rest on earth.) match each item to the correct category.

Arigid tank is divided into two equal parts by a partition. one part of the tank contains 3 kg of compressed liquid water at 400 kpa and 60°c while the other part is evacuated. the partition is now removed, and the water expands to fill the entire tank. determine the entropy change of water during this process, if the final pressure in the tank is 40 kpa. use steam tables.

Does heating a metal wire increase or decrease its electrical resistance? why?

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.