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A particle moves along X-axis with speed6 m/s for the first half distance of a journey and thesecond half distance with a speed 3 m/s. Theaverage speed in the total journey is |
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Answer» Answer: 4 m/s Explanation: Let TOTAL distance of journey by S Time TAKEN for first half journey T1 = Distance / Speed = (S/2) / 6 = S/12 Time taken for SECOND half journey t2 = Distance / Speed = (S/2) / 3 = S/6 Average speed = Total distance / Total time = S / (t1 + t2) = S / (S/12 + S/6) = S / [S(1/12 + 1/6)] = 1 / (1/12 + 1/6) = 1 / (1/12 + 2/12) = 1 / (3/12) = 12 / 3 = 4 m/s |
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