In a lever, the fulcrum isn't always between the load and the effort. In your own words, describe how this changes the usefulness of the lever.

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.

If a spring has a k value of 100 newtons per meter and it is stretched 0.50 meters, what is the restoring force of the spring?

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?