The speed of propagation equals the frequency times the wavelength

Astring that is fixed at both ends has a length of 1.05 m. when the string vibrates at a frequency of 91.0 hz, a standing wave with five loops is formed. (a) what is the wavelength of the waves that travel on the string? (b) what is the speed of the waves? (c) what is the fundamental frequency of the string?

Agas expands from an initial volume of 0.040 m^3 and an initial pressure of 210 kpa to a final volume of 0.065 m^3 while its temperature is kept constant. how much work is done by the system?

2kg of refrigerant 134a undergoes a polytropic process in a piston-cylinder assembly from an initial state of saturated vapor at 2 bar to a final state of 12 bar, 80 degree c. a)determine the work for the process in kj. b)sketch the process on a p-v diagram.