Write the Word or Phrase That Best Completes Each Statement $$d = 25 \cos \left( \frac { 3 \pi } { 4 } t \right)$$

question 135

Essay

Write the word or phrase that best completes each statement or answers the question.
-A boy is flying a model airplane while standing on a straight line. The plane, at the end of a twenty-five foot wire, flies in circles around the boy. The directed distance of the plane from the straight line is found to be
$$d = 25 \cos \left( \frac { 3 \pi } { 4 } t \right)$$ where d is measured in feet and t is the time in seconds. If d > 0, the plane is in front of the boy; if d < 0, the plane is
behind him.
What is the amplitude? What is the period?
Graph d over two periods beginning at t = 0.

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Definitions:

Yerkes-Dodson Law

A theory suggesting that there is an optimal level of arousal for the best performance of a task: too little arousal can lead to insufficient motivation, whereas too much can impair performance.

Moderate Arousal

An optimal level of alertness and physical and mental activation that is conducive to effective, efficient performance on tasks.

Sport Psychologist

A professional who applies psychological principles to athletic activity and exercise to help athletes improve performance, cope with pressure, and recover from injuries.

Arousal Theory

A theory suggesting that people are motivated to maintain an optimal level of arousal, not too low or too high, for their best performance.