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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.
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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