Question
Suppose the ceiling in the previous problem is that of an elevator which is going up with an acceleration of 2.0m/s2. Find the elongations.
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Answer
a = 2m/s2 kl - (2g + 2a) = 0 ⇒ kl = 2g + 2a = 2 × 9.8 + 2 × 2 = 19.6 + 4 = 23.6 
When 1kg body is added total mass (2 + 1)kg = 3kg. elongation be l1 kl1 = 3g + 3a = 3 × 9.8 + 6 = 33.4 
$\Rightarrow\text{I}=\frac{23.6}{100}=0.236\text{m}=0.24\text{m}$
When 1kg body is added total mass (2 + 1)kg = 3kg. elongation be l1 kl1 = 3g + 3a = 3 × 9.8 + 6 = 33.4 $\Rightarrow\text{I}_1=\frac{33.4}{100}=0.0334=0.36$
Further elongation = l1 - l = 0.36 - 0.24 = 0.12m.Need a full question paper?
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