Question

Figure shows three identical springs A, B, C. When a 4 kg weight is hung on A, it descends by 1 cm. When a 6 kg weight is hung on C, it will descent by

                                                   

Solution

Correct option is

3.0 cm

 

Let k be the force constant of each spring. The force F needed to extend the spring A by an amount x is

                             

In figure b, the springs are connected in series. Therefore, the force constant k of the combination is given by

                          

If a force F is applied, the combination will extend by

                        

  

SIMILAR QUESTIONS

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Q2

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Q3

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Q4

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Q5

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Q6

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Q7

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Q8

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Q9

 

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Q10

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