Question

A block of $2kg$ is suspended from the ceiling through a massless spring of spring constant $k=100N/m$. What is the elongation of the spring? If another $1kg$ is added to the block, what would be the further elongation?

Answer 1

Given that,

Mass $M=2kg$

Spring constant $k=100N/m$

Now, the weight force of the block is

$=2gN$

$=2\times 9.8N$

$=19.6N$

Now, the elongation of the spring

$=\frac{19.6}{k}$

$=\frac{19.6}{100}$

$=0.196m$

$=0.2m$

Now, when another $1kg$ block is added,

Then, total weight$=3kg$

Now weight force

$=3g$

$=3\times 9.8$

$=29.4N$

Now the total elongation is

$=\frac{29.4}{100}$

$=0.294$

$=0.3m$

So, the further elongation is

$=0.3-0.2$

$=0.1m$

Hence, the elongation is $0.1m$