According to the "galactic fountain" model, what can create a superbubble emerging into the halo?
A) winds and jets from newly formed protostars
B) a supernova occurring in the halo
C) multiple supernovae occurring near one another around the same time
D) the combined effect of spiral density waves
E) molecular clouds expelled from the galactic center
C) multiple supernovae occurring near one another around the same time
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Specific heat capacity of ice = 2,000 J/kg-°C latent heat of fusion of water = 334,000 J/kg specific heat capacity of water = 4,000 J/kg-°C The 1 kg block of ice melts into water. The amount of heat absorbed by the ice as it melts is __________
Fill in the blank(s) with correct word
A 0.10- gas tank holds 5.0 moles of nitrogen gas (N2), at a temperature of The atomic mass of nitrogen is 14 g/mol, the molecular radius is 3.0 × 10-10 m, and the Boltzmann constant is 1.38 × 10-23 J/K
The root-mean-square speed (thermal speed) of the molecules is closest to A) 570 m/s. B) 810 m/s. C) 410 m/s. D) 22 m/s. E) 99 m/s.
Spherical Mirrors: A statue that is 2.3 cm tall is placed 15 cm in front of a convex mirror. The magnitude of the radius of curvature of the mirror is 18 cm.(a) Is the image real or virtual?(b) How far is the image from the mirror?(c) Is the image upright or inverted?(d) How tall is the image?
What will be an ideal response?
An aluminum light pole weighs 4300 N and supports an arm of weight 700 N, with the arm center of gravity at 1.2 m left of the centroidal axis of the pole. A wind force of 1500 N acts to the right at 7.5 m above the base. The pole cross section at the base has an outside diameter of 235 mm and thickness of 20 mm. The maximum compressive stress at the base is approximately:
(A) 16 MPa
(B) 18 MPa
(C) 21 MPa
(D) 24 MPa