F = ke, spring constant of the three springs in series = 3 x 300 = 900N/m
extension = $\frac{90}{900}$ = 0.1 m
Spring constant of the two springs in series = 2 x 300 = 600N/m,
extension = $\frac{90}{600}$ = 0.15 m
Total extension = 0.15 + 0.10 = 0.25
johnmulu answered the question on April 19, 2017 at 08:57
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