The luminosity of a star is determined by the star's ________ and ________.
A. diameter; surface temperature
B. apparent brightness; surface temperature
C. brightness; temperature
D. distance; surface temperature
E. diameter; distance
Answer: A
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The surface magnetic field of the Sun is found by measurement of the extra width in spectral lines due to the ________ Effect
Fill in the blank(s) with correct word
A particle (mass = 6.7 × 10^?27 kg, charge = 3.2 × 10^?19 C) moves along the positive x axis with a speed of 4.8 × 10^5 m/s. It enters a region of uniform electric field parallel to its motion and comes to rest after moving 2.0 m into the field. What is the magnitude of the electric field?
a. 2.0 kN/C b. 1.5 kN/C c. 1.2 kN/C d. 3.5 kN/C e. 2.4 kN/C
What type of galaxy was observed by Tully and Fisher?
A 6.0-kg object moving 5.0 m/s collides with and sticks to a 2.0-kg object. After the collision the composite object is moving 2.0 m/s in a direction opposite to the initial direction of motion of the 6.0-kg object. Determine the speed of the 2.0-kg object before the collision
a. 15 m/s b. 7.0 m/s c. 8.0 m/s d. 23 m/s e. 11 m/s