An automobile has a mass of 1200 kg. what is its kinetic energy, in kj, relative to the road when traveling at a velocity of 50 km/h? if the vehicle accelerates to 100 km/h in 15 seconds, what is the change in power required?

K.E = 463.04 k J

P = 23.14 Watt

Explanation:

given,

mass of automobile = 1200 kg

velocity = 50 km/h

             = 50 × 0.278

             = 13.9 m/s

kinetic energy =

                        =

        K.E = 115.93 k J

vehicle accelerated to velocity = 100 km/h

                                                    = 100 × 0.2778

                                                    = 27.78 m/s

kinetic energy =

                        =

        K.E = 463.04 k J

work done = change in kinetic energy

                   = 463.04 - 115.93

                   = 347.11 J

Power =

Power =

P = 23.14 Watt

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cathode rays were bent in the same way whenever a magnet was brought near them.