stored is given as follows.
Similarly, the work done by a spring is given by W (^) spring = ½kx 2 . Here’s an example problem.
A block with a mass of 2 kg is attached to a spring with k = 1 N/m. The spring is compressed 10 cm
from equlibrium and than released. How fast is the block traveling when it passes through the
equilibrium point? Neglect friction.
It’s important to recognize that we CANNOT use kinematics to solve this problem! Because the force of a
spring changes as it stretches, the block’s acceleration is not constant. When acceleration isn’t constant,
try using energy conservation.
We begin by writing our statement for conservation of energy.
Now we fill in values for each term. PE here is just in the form of spring potential energy, and there’s no
friction, so we can ignore the W term. Be sure to plug in all values in meters!
Plugging in values for k and m , we have