a square of side 4cm having +2 coulomb charge on each corner . find electrical potential energy of this system

Would corn syrup, molasses, or pancake syrup make a good lubricant in a car engine? explain your answer.

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.

The built in flash in a compact camera is usally capable of giving correct exsposure for distance up to how many meters?