Acomputer is a group of computers linked together to share data and resources.

Sound is a disturbance that travels through a medium as a

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.