Force–Extension Graphs Flashcards

All 5 cards in this deck

What does a force–extension graph look like when force and extension are directly proportional?

A straight line that passes through the origin (constant gradient).

What is the limit of proportionality on a force–extension graph?

The point beyond which extension is no longer directly proportional to force — the line stops being straight and begins to curve.

What is meant by a non-linear relationship between force and extension?

Extension is not directly proportional to force — equal increases in force give different increases in extension, so the graph curves.

On a force–extension graph with force on the vertical axis, what does the gradient of the straight section represent?

The spring constant $k$ (in N/m).

What are the steps to determine a spring constant from a force–extension graph?

e.g. the straight line passes through force $= 5.00$ N at extension $= 0.125$ m

1. Read a correct pair of values from the straight part of the line: $5.00$ N and $0.125$ m
2. Use $k = F/e$ (the gradient): $k = 5.00 / 0.125$
3. $k = 40$ N/m