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Work, Energy And Power

Question
CBSEENPH11026397
Wired Faculty App

Same spring is attached with  2 kg,  3 kg  and  1 kg blocks in three different cases as shown in figure. If  x1 , x2, x3 be the extensions in the spring in the three cases, then

               

  • x1 = 0,  x3 > x2

  • x1 > x2 > x3

  • x3 > x2 > x1

  • x2 > x1 > x3

Solution

D.

x2 > x1 > x3

If T1, T2, T3 are the tensions in the strings in the three cases.

We have

         T1 = 2 m1m2 gm1 + m2

               = 2 × 2 × 2g2 + 2

            T1 = 2g

     T2 = 2 × 3 × 2g3 +2 

      T2 = 2.4 g

     T3 = 2 × 1 × 2g1 + 2

       T3 = 1.33 g

As

           x ∝ T

and    T2 > T1 > T3

∴   x2 > x1 > x3

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