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Question
Two friends leave Delhi for Chandigarh in their cars. A starts at 5 am and moves with a constant speed of 30 km/h, whereas B starts at 6 am and moves with a constant speed of 40 kmh-1. Plot the distance-time graph for their motion and find at what time the two friends will meet and at what distance from Delhi.
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Solution
So we can see that the two friends wiil meet at 9 a.m ant till then they cover a distance of u x t = u' xt' = 30 x4 = 40 x 3 =120 km So they are 120 km away from Delhi when they meet at 9 a.m.
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