Controlling the amount of current in a circuit by opposing the flow of charge is a function of which circuit component?
A. Resistor
B. Capacitor
C. Transistor
D. Battery

Iron reacts with sulfur to form iron sulfide. if 60 grams of iron reacts with sulfur to produce 90 grams of iron sulfide, how much sulfur has been used in the chemical reaction?

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

Name two kinds of practical electric pumps.