What changed in our understanding of the moon and moon-earth system as a result of humans landing on the moon’s surface?

Wo audio speakers are placed on a vertical rail. speaker a is placed at head-level while speaker b is place at some variable height, \delta yδy, above speaker a. both speakers receive simultaneous input from a sine-wave generator so the speakers each produce a pure sinusoidal sound wave with a wavelength of 0.531 meters. calculate the lowest height that speaker b can be placed above speaker a to produce a minimum of sound heard by person standing \delta x = 7.86δx=7.86 meters directly in front of speaker a.

Wavelength,frequency,and energy are related.what happens to a wave as it’s wavelength gets shorter?

To a of 4 x hz is 1. 0. mm nm nm