In a steam engine, steam at 140°C in a turbine does work on an external system, and the steam leaves the turbine at 100°C. The efficiency of the steam engine is 5%. The relevant physical principle is a. the second law of thermodynamics
b. the first law of thermodynamics
c. operation of a heat pump
d. specific heat capacity

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.

Movement that is like a t a type of wave that transfers energy where the particles in the medium move in a circle motion while the energy travels left or right. a type of wave that transfers energy where the particles in the medium move perpendicular to the direction in which the energy is traveling. transfers energy from one location to another a type of wave that transfers energy where the particles in the medium move parallel to the direction in which the energy is traveling. movement that is back and forth, like an equal sign = 1. wave 2. parallel movement 3. perpendicular movement 4. transverse wave 5. longitudinal wave 6. surface wave

How many moles are in 1.26*10^24 particles in significant figures