Two cars approaching each other, The first car is a police car that moves at 72 km/h while the second car moves at 90 km/h, The police car started its siren with a frequency of 650 Hz. If the speed of the sound is 350 m/s, then what is the frequency of the sound heard by the driver of the second car from the police car?

An engine undergoes a cycle as shown in the diagram. during a complete cycle the work done by the gas is 28.5×103 j and the energy transferred thermally out is 99.4×103 j. there are 1.5×1024 gas molecules and they have three active degrees of freedom. 6. (6 pts) during which process(es) is energy transferred thermally into the gas? a. 1→2 b. 2→3 c. 4→1 d. 1→2 and 4→1 e. none of the above

The magnitude of the amount of energy released by burning a fuel source, measured in energy per unit mass, is called its fuel value. note that the fuel value is the negative of the isobaric specific heat of combustion for the fuel. if all the energy obtained from burning 1.23 pounds of butane with a fuel value of 10.85 kcal/g is used to heat 128.0 kg of water at an initial temperature of 18.3 °c, what is the final temperature? note that 1 lb = 453.6 g.

Aheat engine that operates on a carnot cycle has an efficiency of 0.420 when its low-temperature reservoir is at 10 ∘c.part aby how many degrees celsius must you increase the temperature of the high-temperature reservoir to increase the efficiency to 0.600 if you continue to use the same low-temperature reservoir?