When an electron drops from a higher energy level to a lower one, energy is emitted. In comparison, how much energy is required to reverse the process, going from the lower level to the higher level?
A) less energy
B) the same energy
C) more energy
Question 2
A roller coaster car is on a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minimum value for its centripetal acceleration at this point?
A) g downward
B) 0.5g downward
C) 2g downward
D) g upward
E) 2g upward
Energy flow through an ecosystem.
Nuclear division at the DNA level
Electron microscopic image of dinoflagellates
fusion for energy
Comparison of Two Compromises
Electromagnetic Spectrum of Radiant Energy