A spring balance reads forces in Newton. The scale is 20 cm long and read from 0 to 60 N. Find potential energy of spring when the scale reads 20 N.

Explanation

To find the potential energy of the spring when the scale reads 20 N, we will follow these steps:

### Step 1: Determine the Spring Constant (k)
The spring balance reads from 0 to 60 N over a length of 20 cm. We can use Hooke's Law, which states that the force (F) exerted by a spring is proportional to its extension (x) from its equilibrium position:

\[ F = k \cdot x \]

Where:
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