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The kinetic energy of an object of mass, m moving with a velocity of 10 m/s is 50 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 ? |
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Answer» We know that K.E= \frac{1}{2} mv^221mv2⇒ K.E = \frac{1}{2} mv^221mv2⇒ 25 = \frac{1}{2}21 m 5^252⇒ m = 2 kg1st CASEIF velocity is doubledthen,velocity of the OBJECT = 10 m/smass OS the object = 2 kg⇒ K.E = \frac{1}{2} mv^221mv2⇒ K.E = \frac{1}{2}21 2 × 10²⇒ K.E = 100 joule.2nd CaseIf velocity is three timesThen,velocity of the object = 15 m/smass os the object = 2 kg⇒ K.E = \frac{1}{2} mv^221mv2⇒ K.E = \frac{1}{2}21 2 × 15²⇒ K.E = 225 joule.Hence, kinetic energy when its velocity is INCREASED three times 225 J. |
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