Aporsche 944 turbo has a rated engine power of 217hp . 30% of the power is lost in the drive train, and 70% reaches the wheels. the total mass of the car and driver is 1520 kg, and two-thirds of the weight is over the drive wheels.

a) what is the maximum acceleration of the porsche on a concrete surface where μs=1?

b) what is the speed of the porsche at maximum power output?

c) if the porsche accelerates at amax , how long does it take until it reaches the maximum power output?

Explanation:

(a)  It is given that two-third of weight is over the drive wheels. So, mathematically, w = .

Hence, maximum force is expressed as follows.

Hence, the maximum acceleration is calculated as follows.

                          =

                          = 6.53

Hence, the maximum acceleration of the Porsche on a concrete surface where μs = 1 is 6.53 .

(b)  Since, 30% of the power is lost in the drive train. So, the new power is 70% of .

That is,   new power =

Now, the expression for power in terms of force and velocity is as follows.

                      P =

Therefore, speed of the Porsche at maximum power output is as follows.

                      =

                      = 11.568 m/s

                      = 11.57 m/s

Therefore, speed of the Porsche at maximum power output is 11.57 m/s.

(c)   The time taken will be calculated as follows.

             time =

                     =

                     = 1.77 s

Therefore, the Porsche takes 1.77 sec until it reaches the maximum power output.

answer: decibel

explanation:

answer: option c.

explanation: