A1.0 × 10^3-kilogram car travels at a constant
speed of 20. meters per second around a
horizontal circular track. the diameter of the
track is 1.0 × 10^2 meters. the magnitude of the
car’s centripetal acceleration is
(1) 0.20 m/s2 (3) 8.0 m/s2
(2) 2.0 m/s2 (4) 4.0 m/s2

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.

If steel is more dense that lake water, why can a boat float

Atank is filled with an ideal gas at 400 k and pressure of 1.00 atm . part a the tank is heated until the pressure of the gas in the tank doubles. what is the temperature of the gas?