Did ernest rutherford have to overcome any obstacles to become a scientist? if yes, what were those obstacles?

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.

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant