Recitation Week 3
Chapter 2
Problem 2.5.A position-time graph for a particle moving along thexaxis is shown in Figure P2.5.(a)Find the averagevelocity in the time intervalt= 1.
(b)Determine the instantaneous velocity att= 2.00 sby measuring theslope of the tangent to the graph.(c)At what value oftis the velocity zero?
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Problem 2.11.A hare and a tortoise compete in a race over a straight course1.00 kmlong. The tortoise crawls at a speedof0.200 m/stoward the finish line. The hare runs at a speed of8.00 m/stoward the finish line for0.800 kmand then stopsto tease the slow-moving tortoise as the tortoise eventually passes by. The hare waits for a while after the tortoise passes byand then runs toward the finish line again at8.00 m/s. Both the hare and the tortise cross the finish line at exactly the sameinstant. Assume both animals, when moving, move steadily at their respective speeds.(a)How far is the tortoise from thefinish line when the hare resumes the race?(b)For how long in time was the hare stationary?Sometimes it is useful to draw a graph to get a feel for what’s going on.