Sound waves in air are a series of
a. periodic disturbances.
b. periodic condensations and rarefactions.
c. high- and low-pressure regions.
d. all of the above e. none of the above

An athlete is holding 24 lb of weights at a height of 6 inches above the stack as shown. to lower the weights, she applies a constant force of 5 lb to the handle. determine the velocity of the weights immediately before they hit the stack.