What would we need to know to calculate both work and power? a. energy, force, and time b. force, distance, and time c. force, mass, and distance d. mass, force, and energy

Mechanical energy is when the amount of kinetic and potential energies added together remains the same. conserved created lost

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.

What is the efficiency of an engine that does 80 j of work and exhausts 320 j of heat while taking in 400 j of heat ? a. 10% b. 20% c. 80% d. 25%