How Do You Calculate Wavelength in a Standing Wave Scenario?

[AnomalyCoder]

Homework Statement

Sally sue and her partner hold a spring 4 meters apart. There were 5 nodes in the standing waves produced. Sally moved her hand from the rest position back and forth along the floor 20 times in 4 seconds. F

Homework Equations

The Attempt at a Solution

Since there are 5 nodes, we are considering 4 waves, therefore 4 meters/4 waves = 1 meter.
However, someone else got they answer to be 2. What is the correct solution and why?

 

[Clever-Name]

Draw out a picture where you have 5 nodes, see how many FULL waves you have.

 

[WatermelonPig]

A full wave includes both a crest and a trough not just one or the other.

 

[wbandersonjr]

Yes a wavelength includes one crest and one trough in the picture of this problem.