Elastic Potential Energy Flashcards

All 4 cards in this deck

What is the equation for the energy transferred in stretching a spring, with units?

$E = \tfrac{1}{2} \times k \times x^2$; energy in J, spring constant in N/m, extension in m.

How can the work done in stretching a spring be found from its force–extension graph?

It is the area under the graph. For a straight line through the origin, work done = ½ × force × extension (J, with force in N and extension in m).

True or false? Doubling the extension of a spring doubles the energy stored in it.

False. Energy depends on $x^2$, so doubling the extension gives four times the energy.

When a spring is distorted elastically, how does the work done on it compare with the energy in its elastic potential energy store?

They are equal: all the work done is stored as elastic potential energy.