What is a brown dwarf?

1.there no such thing.
2.a star no longer undergoing nuclear fusion.
3.a star right as it undergoes nuclear fusion.
4.an object that is big, but not massive enough to undergo brackets fusion

Write the equation for momentum, first using symbols for the variables, then using words for the variables.

Aspacecraft that renters the earth’s atmosphere drastically slows down. the amount of kinetic energy the spacecraft has as it reenters the earths atmosphere

Listed following are various physical situations that describe how light interacts with matter. match these to the appropriate category. 1) transmission? -visible light meets clear glass -visible light does not pass through a black wall -red light hits a red sweatshirt -light comes from your computer screen -cell phone signals pass through walls -blue light hits a red sweatshirt -white light hits a white piece of paper -light comes from a light bulb