Question

If the length of a `19 cm` spring increases to `54 cm` when a `4 kg` weight is hanging from it, what is the spring's constant?

Answer 1

The spring constant is 112 N/m.

Explanation:

Spring constant it typically given in units of N/m, so I will convert the spring lengths to m. 19 cm = 0.19 m & 54 cm = 0.54 m

The weight of that 4 kg mass is `m*g = 4 kg*9.8 m/s^2 = 39.2 N`.
The amount of stretch that the weight caused was
`0.54 m - 0.19 m = 0.35 m`

Therefore the spring constant is `(39.2 N)/(0.35 m) = 112 N/m`

I hope this helps,
Steve