The kinetic energy of an object of mass m moving with a velocity of 5 m/s is 25 J. What will be its kinetic energy when its velocity is doubled? What will be its kinetic energy when its velocity is increased three times?
We know that kinetic energy (KE) = ½ × mass × velocity².
When velocity is doubled:
New velocity = 2 × 5 = 10 m/s
New KE = ½ × m × (10)² = ½ × m × 100
Since original KE = 25 J, new KE = 4 × 25 = 100 J
When velocity is tripled:
New velocity = 3 × 5 = 15 m/s
New KE = ½ × m × (15)² = ½ × m × 225
New KE = 9 × 25 = 225 J
So, the kinetic energy will be 100 J when the velocity is doubled and 225 J when the velocity is tripled.
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