Lance threw a ball straight up into the air. The ball’s gravitational potential energy at its peak height was 0.4 joules, and its speed when it hit the ground was 4 meters per second. What was the mass of the ball?

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.

In 1980, alfa romeo introduced the first system to smooth a rough idle caused by ignition and camshaft timing changes.

Name three different units of energy used to measure heat and describe what type of situations each is usually used.