Dos masas están conectadas por una cuerda ligera que pasa por una polea sin rozamiento. Determine la aceleración de las masas y la tensión de la cuerda si m Kg A  20 , m Kg B  50 y  0.20  K A Y B

Which is an example of gaining a static charge by conduction? a) rubbing a balloon against your hair. b) shuffling your shoes across a carpet. c) bringing a charged rod near an electroscope. d) touching your car on a cold day and getting a shock.

Air initially at 0.75 bar, 1000 k, and occupying a volume of 0.12 m^3 undergoes two processes. process 1-2: the air is compressed isothermally until the volume is halved. process 2-3: the air undergoes a constant pressure process until the volume is halved again. assume ideal gas behavior. a) determine the mass of the air, in kg. b) the work and the heat transfer for each of the two processes, in kj. (100 kj = 1 bar . m^3)

In the first law of thermodynamics, triangle e=q-w, what does q stand for