Answers

2014-06-08T20:19:04+05:30
S = ut + at²/2
15 = 3u + 9a/2
30 = 6u + 9a --------------------(1)
63 = 7u + 49a/2
126 = 14u + 49a --------------------------(2)
7*(1) - 3*(2)
210 - 378 = 63a - 147a
168 = 84a
a = 2m/s^2
put a = 2 in equation (1)
30 = 6u + 18
u = 2m/s
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