An open system starts with 52 J of mechanical energy. The energy changes to 45 J of mechanical energy and 2 J of thermal energy. What is the final total
energy of the system?
A. 54J
B. 47 J
C. 9 J
D. 50 J

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j ?

How are series and parallel circuits simililar? both have multiple paths for electrons to travel. both require resistors in their circuits. both require a switch to complete the circuit. both have at least one path for electrons to travel.

An object weigh 40n in air ,weigh 20n when submerged in water,and 30n when submerged in a liquid of unknown liquid density.what is the density of unknown of liquid?