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Calculate the work required to be done to stop a car of l500 moving at a velocity of 72 km/h |
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Answer» ne to stop a car = kinetic energy of the car .Formula Kinetic energy = 1/2 × m v²Given :Mass ( m ) = 1500 kgvelocity ( v ) = 72 km/hrK = 1/2 m v² = 1/2 × ( 1500 kg ) × ( velocity )²Hold on !72 km/hr should be CONVERTED to m/s72 km = 72000 m1 h = 3600 s72 km/hr = 72,000 / 3600 m/s= > 20 m/sNow : K = 1/2 × 1500 × ( 20 )² J= > K = 750 × 400 J= > K = 3,00,000 JANSWER :The work DONE is 3.0 × 10⁵ |
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