Springs in Series and in Parallel

Theory

Two equal springs $k$ in series behave like $k_{eq}=\frac{k}{2}$ (softer); in parallel, like $k_{eq}=2k$ (stiffer). With $T=2\pi \sqrt{m/k_{eq}}$: series period is $\sqrt{2}$ larger, parallel period is $\sqrt{2}$ smaller.

What to observe

• k = 40 N/m, m = 1 kg: single ≈ 0.99 s; series ≈ 1.40 s; parallel ≈ 0.70 s.
• The parallel system oscillates fastest.

Try this

• Measure the periods in the graph (select each mass).
• Change k in one of the springs.

Also available in: Associação de molas em série e em paralelo (Português) · Resortes en serie y en paralelo (Español)