how will the energy density of the electric field in a capacitor change if you kept the same voltage between the plates, but reduced the distance between the plates to half of the original distance?

In a heat engine if 1000 j of heat enters the system and the piston does 500j of work, what is the final internal energy of the system if the inital energy was 2000 j1.write the equation2.list out your known variables 3. plug the numbers into the equations4.solve 5.write your solution statement that includes initial energy and final energy added.