Please help MasteringPhysics: Homework 9 - Google Chrome https://session.masteri
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Please help
MasteringPhysics: Homework 9 - Google Chrome https://session.masteringphysics.com/myct/itemView?assignmentProblemID 626818138offset prev PHY 243 Sp16 Principles of Physics I - Tarini Signed in as basem fodah Help Close Homework 9 A Car with Constant Power Resources « previous 4 of 18 next » A Car with Constant Power Part A The engine in an imaginary sports car can provide constant power to the wheels over a range of speeds from 0 to 70 miles per hour (mph). At full power, the car can accelerate from zero to 31.0 mph in time 1.10 At full power, how long would it take for the car to accelerate from 0 to 62.0 mph? Neglect friction and air resistance Express your answer in seconds. 4.40 s Submit Hints My Answers Give Up Review Part Correct Of course, neglecting friction, especially air friction, is completely unrealistic at such speeds Part B A more realistic car would cause the wheels to spin in a manner that would result in the ground pushing it forward with a constant force (in contrast to the constant power in Part A). If such a sports car went from zero to 31.0 mph in time 1.10 s, how long would it take to go from zero to 62.0 mph? Express your answer numerically, in seconds 6:50 PM 5/30/2016 Ask me anything ENGExplanation / Answer
ANSWER
Under constant Force, you get constant acceleration.
The only formula you need is speed = acceleration * time
The acceleration is 31 mph / 1.1 secs
Now 62 mph = (31mph / 1.1 secs) * time to accelerate to 62mph
So the time is,
t = 1.1 * 62 / 31
t = 2.2 s
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