Eta Carinae is an example of a:
A) black hole.
B) supermassive star.
C) red dwarf.
D) nebula.
E) stellar nursery.
B
You might also like to view...
____________ in Saturn's rings is/are produced by the gravitational interaction of Mimas with the particles in the rings and appears as a large ____________ in the rings
a. Cassini's division; gap b. Cassini's division; clump c. Moons; gap d. Moons; clump
Our Sun is a first-generation star.
a. true b. false
A steam pipe 200-mm in diameter passes through a large basement room. The temperature of the pipe wall is 500°C, while that of the ambient air in the room is 20°C. Determine the heat transfer rate by convection and radiation per unit length of steam pipe if the emissivity of the pipe surface is 0.8 and the natural convection heat transfer coefficient has been determined to be 10 W/(m2 K).
GIVEN
FIND
- Heat transfer rate by convection and radiation per unit length of the steam pipe (q/L)
ASSUMPTIONS
- Steady state prevails
- The walls of the room are at the same temperature as the air in the room
- 
ASSUMPTIONS
- Steady state prevails
- The walls of the room are at the same temperature as the air in the room
- 
SKETCH
The Sun appears to be red as it sets because:
1.Air absorbs red light less than other frequencies (i.e., acts like a red filter). 2.The sunlight has a red-shift when you're moving fastest away from it. 3.The Sun cools down to 5000 K each evening. 4.Light is refracted as it enters the atmosphere. 5.The Sun dies in a glorious fireball each evening and is reborn each morning. 6.None of the above.