The Tacoma narrows bridge collapsed due to? A. Refraction
B. Reflection
C. Diffraction
D. Resonance

If steel is more dense that lake water, why can a boat float

What is the most useful equation for electric power?

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.