Calculate the energy for vacancy formation in nickel (Ni), given that the equilibrium number of vacancies at 850C (1123 K) is 4.7 1022 m3 . The atomic weight and density (at 850C) for Ni are, respectively, 58.69 g/mol and 8.80 g/cm3 .

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

Examine the equation. 23490th→23088ra+42he what kind of barrier would you need to block the radioactive particles from this reaction? a.a piece of paper b.a sheet of aluminum foil c. a two-inch block of lead d. a solid concrete block

How does an observation about an object differ from an inference about that object