At its widest point, the diameter of a bottlenose dolphin is 0.50 m. bottlenose dolphins are particularly sleek, having a drag coefficient of only about 0.090. a. what is the drag force acting on such a dolphin swimming at 7.5 m/s?
b. using the dolphinâs diameter as its characteristic length, what is the reynolds number as it swims at this speed in 20â° c water?

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.

Aball is thrown from the top of a building with an initial velocity of 21.9 m/s straight upward, at an initial height of 51.6 m above the ground. the ball just misses the edge of the roof on its way down, as shown in the figure. (a) determine the time needed for the ball to reach its maximum height. (b) determine the maximum height. (c) determine the time needed for the ball to return to the height from which it was thrown, and the velocity of the ball at that instant. (d) determine the time needed for the ball to reach the ground. (e) determine the velocity and position of the ball at t = 5.35 s.

Acar traveling at a constant speed of 22.0 m/s passes a trooper hidden behind a billboard. one second after the speeding car passes the billboard, the trooper sets off in chase with a constant acceleration of 3.50 m/s2. how long does it take the trooper to overtake the speeding car? solve this problem by a graphical method. on the same graph, plot position versus time for the car and the trooper.