A0.66-kg block is hung from and stretches a spring that is attached to the ceiling. a second block is attached to the first one, and the amount that the spring stretches from its unstrained length increases by a factor of 7. what is the mass of the second block?

So the mass of second block will be 3.96 kg

Explanation:

We have given mass of the block m = 0.66 kg

The spring is stanched by the factor 7

From hook's law we know that mg = kx

So

Let the mass of second block is M

So

Putting the value of m = 0.66 and  

So the mass of second block will be 3.96 kg

there was no answer choices but i think its representative

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