Planet B has a period of 51 days and a radius of 7 x 10^6​ ​ m. Planet A has a radius of 9.0 x 10^6​ m . Calculate the period of Planet A.

Which notation is used to represent an alpha particle? a. b. c. d.

Consider a hydrogen atom in the ground state. what is the energy of its electron? =e= jj now consider an excited‑state hydrogen atom. what is the energy of the electron in the =5n=5 level? =e5= j

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.