Question

A 0.66-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?

Answer 1

So the mass of second block will be 3.96 kg

Step-by-step 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
`k=(mg)/(x)`

Let the mass of second block is M

So
`(M+m)g=k(7x)`

Putting the value of m = 0.66 and
`k=(mg)/(x)`

`(M+0.66)g=(mg)/(x)(7x)`

`(M+0.66)=7m`

`(M+0.66)=7* 0.66=4.62`

`M=3.96kg`

So the mass of second block will be 3.96 kg