A Floating Leaf Bobs Up and Down Two Complete Cycles $10 \mathrm {~m} / \mathrm { s }$

Short Answer

A floating leaf bobs up and down two complete cycles each second as water waves pass by five meters apart.How fast are the waves moving? a. $10 \mathrm {~m} / \mathrm { s }$
b. $20 \mathrm {~m} / \mathrm { s }$
c. $30 \mathrm {~m} / \mathrm { s }$
d. $40 \mathrm {~m} / \mathrm { s }$