1.) A pencil is dropped from the top of a very tall bridge and hits the ground 3.2 s later.
A.) With what velocity did the pencil hit the river below?
B.) How far did the pencil fall?
2.)
The same pencil is dropped and falls 30 m.
A.) How long did it take the pencil to hit the ground?
B) With what velocity did the pencil hit the ground?

The particle in a two-dimensional well is a useful model for the motion of electrons around the indole ring (3), the conjugated cycle found in the side chain of tryptophan. we may regard indole as a rectangle with sides of length 280 pm and 450 pm, with 10 electrons in the conjugated p system. as in case study 9.1, we assume that in the ground state of the molecule each quantized level is occupied by two electrons. (a) calculate the energy of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels. 9.27 electrons around the porphine ring (4), the conjugated macrocycle that forms the structural basis of the heme group and the chlorophylls. we may treat the group as a circular ring of radius 440 pm, with 20 electrons in the conjugated system moving along the perimeter of the ring. as in exercise 9.26, assume that in the ground state of the molecule quantized each level is occupied by two electrons. (a) calculate the energy and angular momentum of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels.

Which branches of natural science include the study of an organism that lived 10 million years ago

J. j. thomson’s experiment disproved the theory that an atom