Edwin Hubble used a telescope and observed fuzzy blobs of light off in the distance. He realized that these lights were: O Stars O Galaxies O Universes O Planets

Aforce of 9.00 newtons acts at an angle of 19.0 to the horizontal. what is its component in the horizontal direction?

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.

Which of these has some mechanical energy? a. an atom b. heat inside earth c. a book on a shelf d. the fire from a lit match