A car can go from 0 to 100 km/h in 8 seconds. At what time does car reach 50 km/h.

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The car can accelerate at a maximum rate and its speed can increase from 0 km/h to 100 km/h in 8 seconds. 100 km/h in terms of m/s is equal to (100*1000)/3600 = 27.77 m/s. The maximum acceleration of the car is given by a = (v - u)/t = (27.77 - 0)/10 = 2.77 m/s^2.

The time taken by the car to reach a speed of 50 km/h has to be determined. 50 km/h in terms of m/s is equivalent to 50*1000/3600 = 13.88 m/s.

Using the relation v = u + a*t, and substituting a = 2.77, we get:

13.88 = 0 + 2.77*t

=> t = 5 s

The minimum time taken by the car to reach 50 km/h is 5 s.

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