BIO The Flying Leap of a Flea.? High-speed motion pictures (3500 frames/second) of a jumping 210-µg flea yielded the data to plot the flea’s acceleration as a function of time, as shown in ?Fig. P5.78?. (See “The Flying Leap of the Flea,” by M. Rothschild et al., ?Scientific American,? November 1973.) This flea was about 2 mm long and jumped at a nearly vertical takeoff angle. Using the graph, (a) find the ?initial? net external force on the flea. How does it compare to the flea’s weight? (b) Find the ?maximum? net external force on this jumping flea. When does this maximum force occur? (c) Use the graph to find the flea’s maximum speed.
Solution to 75P Step 1 From the graph, 2 Initial a=612.5m/s ………..(a/g=62.5) Mass of the flea=210g Step 2 (a) Initial acceleration of the flea=F F=ma F=210g x612.5 -4 F=1.26x10 N