1.

The power of engine of a car of mass 1200 kg is25 kW. The minimum time required to reach a velocityof 90 km/h by the car after starting from rest is(1) 15 s(3) 60 s1.(2) 25 s(4) 12 s

Answer»

Velocity = 90 km/hr = 25 m/s.

Power = 25 kW = 25,000 W.

Work = Kinetic energy

∴ W =1/2 mv²

⇒ W = 375000

Since, Power = Work/time.

⇒ Time = Work/Power

⇒ Time = 375000/25000

∴ t = 15 s.



Discussion

No Comment Found

Related InterviewSolutions