Basic mechanics question. Help.

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1

<p>A mattress is 18 cm deep. When a 75 kg sleeper lies on it, 15 of the springs are compressed by an average of 0.5 cm. Calculate the force needed to compress each spring by 1cm.</p>

<p>Can you explain the procedure while answering? Thank you.</p>

2

<p>F=kx, we want double the x, so we want double the F
F=ma=(75kg)(10m/s^2)=750N. 2F=1,500N</p>

3

<p>^Yes, except that the question wants the force per spring: 1500 N / 15 = 100 N.</p>