During a process in which 1556 foot-pounds of positive work is done by a closed stationary system, the internal energy decreases by 5 British thermal units. The heat transfer is most nearly:. 1. 10 Btu added.
2. 3 Btu extracted.
3. 3 Btu added.
4. 7 Btu extracted.
5. 7 Btu added.

What is hidden during a lunar eclipse? isn't the moon hidden?

Afisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. it takes a time of 2.20 s for the boat to travel from its highest point to its lowest, a total distance of 0.670 m . the fisherman sees that the wave crests are spaced a horizontal distance of 5.80 m apart. (a) how much is the wavelength? (b) find the period of the wave. (c) how fast are the waves traveling? (d) what is the amplitude a of each wave?

If the new moon happens on january 15th, what shape will it be on february 6th?