How is the age of the galaxy determined?
a. Measuring the metallicity of Population II stars.
b. Finding the turnoff point in the H-R diagram of globular clusters.
c. From the motion of stars in the galactic halo.
d. Counting the number of open clusters in the spiral arms.
B
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High mass stars are typically found on the ________ of the main sequence
A) upper right B) lower left C) upper left D) lower right E) center
The distribution of Population II stars and globular clusters shows the Galaxy was more ________ in shape when it formed than it is now
Fill in the blank(s) with correct word
A uniform ball with diameter of 10 cm rolls without slipping on a horizontal tabletop. The moment of inertia of the ball about an axis through its center is 2.2 × 10-3 kg ? m2,
and the translational speed of its center is 0.45 m/s. (a) What is its angular speed of the ball about its center of mass? (b) What is the rotational kinetic energy of the ball? (c) What is the ball's angular momentum about its center of mass?
Ethyl glycol at 90ºC flows at 10 m/s through 2 mm diameter heat exchanger tubes. The tube surface temperature is 30ºC at the entrance and the tube is 60 cm long. Estimate the outlet temperature of the ethyl glycol and the outlet tube surface temperature.
What will be an ideal response?