What is the main sequence?
A. a region of cool, luminous stars in the upper right corner of the H-R diagram
B. a region of hot dim stars in the lower left corner of the H-R diagram
C. the order in which spectral types are listed
D. an approximately straight line on the H-R diagram along which 90% of stars lay
Answer: D
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What are the dark regions that give the Sun's photosphere a mottled appearance?
a. CMEs b. sunspots c. spicules d. granules e. flares
A viscous fluid is flowing through a small tube at a rate of 
If the pressure difference between one end of the tube and the other is doubled and the radius is also doubled, then what is the rate of flow of the fluid?
A. 
B. 
C. 
D. 
E. 
When is the angular momentum of a system constant?
A) Only when its total kinetic energy is constant. B) Only when the linear momentum and the energy are constant. C) Only when no net external torque is exerted on the system. D) Only when the moment of inertia is constant.
A container with rigid walls is filled with 4 mol of air with CV = 2.5R. How much does the internal (thermal) energy change if the temperature of the air rises from 16°C to 437°C? The ideal gas constant is R = 8.314 J/mol ? K
A) 35 kJ B) 421 J C) 3.5 kJ D) 8.75 kJ