I am not understanding a concept in electronics. When people say positive and negative charges I get confused as electrons are negatively charged and if they become positive they would be antimatter, which doesn't happen. So if someone could clear up why people say positive and negative charges I would be grateful.

What happens to the velocity of the car when the upward pull of the cable is greater than the downward pull of gravity as the car rises toward the top?

Which statement best describes how private industry decides where to spend the money on research and development

Avehicle has an oil leak that is causing the entire oil pan to be wet, but inspection reveals no exact source after cleaning off the oil residue. technician a says to install a fluorescent dye in the crankcase and operate the engine, then re-inspect for leaks with a special light (black light). technician b says the oil leak may be coming from a source at the top of the engine, such as a valve cover gasket. who is correct?