Arigid tank whose volume is 2 m3, initially containing air at 1 bar, 295 k, is connected by a valve to a large vessel holding air at 6 bar, 295 k. the valve is opened only as long as required to fill the tank with air to a pressure of 6 bar and a temperature of 380 k. assuming the ideal gas model for the air, determine the heat transfer between the tank contents and the surroundings, in kj.

Acatapult is tested by roman legionnaires. they tabulate the results in a papyrus and 2000 years later the archaeological team reads (distances translated into modern units): range = 0.4 km; angle of launch = π/5 rad; landing height = launch height. what is the initial velocity of launch of the boulders if air resistance is negligible?

Is it possible to use the energy from two atoms colliding to create a clean burning lasting fuel source with a large amount of force? is it also possible to harness that energy from the two atoms colliding to create a clean energy source that will last for years from just two atoms colliding. is there a possibility to control and store that energy for years but slowly let the energy out enough to power cities cheaper and faster.

Exercise 2. find the wavelength of a photon emitted when an electron jumps from the n = 3 energy level down to the n = 2 energy level. where is this photon in the electromagnetic spectrum?