As the driver steps on the gas pedal, a car of mass 1 160 kg accelerates from rest. During the first few seconds of motion, the car’s acceleration increases with time according to the expression
where t is in seconds and a is in m/s2. (a) What is the change in kinetic energy of the car during the interval from t = 0 to t = 2.50 s? (b) What is the minimum average power output of the engine over this time interval? (c) Why is the value in part (b) described as the minimum value?
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Physics for Scientists and Engineers with Modern Physics
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