SSC
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following requires the most power (assuming all are lifted to the same height)?
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Lifting Berto in 5 seconds
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Lifting Ms. Fio in 10 seconds
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Lifting Berto in 1 second
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Lifting Ms. Fio in 1 second
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Explanation:
Detailed explanation-1: -The kinetic energy of the mass being lifted can be found with the equation 12mv2. This applies for the instantaneous velocity while the mass is being lifted. When the velocity is 0, when you begin lifting and when you stop lifted, the kinetic energy is 0. This is because 12m(0)2=0.
Detailed explanation-2: -So, the body will posses 4900 joules of energy. It is the required solution.
Detailed explanation-3: -A weightlifter holds a 100 kg barbell above her head. Is work done? Yes because there is a force applied to the barbell and the force causes a displacement of the barbell.
There is 1 question to complete.