Concept explainers
An object that moves in one dimension has the velocity-versus-time graph shown in Figure P2.52. At time t = 0, the object has position x = 0.
a. At time t = 5 s. is the acceleration of the object positive, negative, or zero? Explain.
b. At time t = 8 s, is the object speeding up, showing down, or moving with constant speed? Explain.
c. Write an expression for the position of the object as a function of time. Explain how you use the graph to obtain your answer.
d. Use your expression from part (c) to determine the time (if any) at which the object reaches its maximum position. Check your results by examining the graph. Hint: To get started with finding the maximum of a function, take the derivative and set it equal to zero.
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Chapter 2 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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