If the period of a wave is 15 seconds, how many wavelengths pass a certain point in 2 minutes?

Hello
The period of a wave is the time it takes between two complete oscillations of the wave itself, i.e. it is the time that occurs between two consecutive wavelengths. Therefore, if we want to calculate how many wavelengths pass a certain point in , we need to divide the total time for the period of the wave, T:

So, the answer is 8 wavelengths.

The radiation of the fire causes the saucepan to heat up. the conduction of the saucepan then to distribute the heat over the saucepan and to give heat to the water. the convection of the water distributing the heat within the water, till all the water is boiling