A 22.0 kg bucket of concrete is connected over a very light frictionless pulley to a 375 N box on the roof of a building as shown in the figure. There is no appreciable friction on the box, since it is on roller bearings. The box starts from rest. How fast is the bucket moving after it has fallen 1.50 m (assuming that the box has not yet reached the edge of the roof)? A. 3.28 m/s
B. 5.20 m/s
C. 4.67 m/s
D. 3.00 m/s

What are chlorofluorocarbons and what impact do they have on the atmosphere?

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.

Asmall 21 kilogram canoe is floating downriver at a speed of 1 m/s. what is the canoe's kinetic energy?