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प्रश्न
A girl is carrying a school bag of 3 kg mass on her back and moves 200 m on a levelled road. If the value of g be 10 m/s2, the work done by the girl against the gravitational force will be :
विकल्प
6000 J
0.6 J
0 J
6 J
उत्तर
The girl is moving with the bag on a levelled road. Her direction of motion is perpendicular to the direction of gravitational force. So, work done by the girl against gravity is zero. Therefore, the answer is 0 J
(c) 0 J
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