A star has absolute luminosity equal to that of the Sun (1.5 × 108 km from the Earth) but is 10 pc away from the Earth. By what factor will it appear dimmer than the Sun?
A)
2 × 10-9
B)
2 × 10-11
C)
2 × 10-13
D)
2 × 10-15
E)
2 × 10-17
C
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The three laws dealing with the creation of various spectra are due to:
A) Newton. B) Fraunhofer. C) Kirchhoff. D) Bohr. E) Einstein.
The curved section of a horizontal highway is a circular unbanked arc of radius 740 m
If the coefficient of static friction between this roadway and typical tires is 0.40, what would be the maximum safe driving speed for this horizontal curved section of highway? A) 54 m/s B) 48 m/s C) 52 m/s D) 46 m/s E) 50 m/s
A stone is thrown at an angle of 30° above the horizontal from the top edge of a cliff with an initial speed of 14 m/s. A stop watch measures the stone's trajectory time from top of cliff to bottom to be 7.1 s. What is the height of the cliff? Note: g = 9.8 m/s2 and air resistance is negligible
a. 58 m c. 120 m b. 114 m d. 197 m
Quantum mechanics is
A) a branch of physics that applies on very small scales. B) the idea that mechanics can be understood only if we first understand quantums. C) the idea that quantitative methods are needed to understand physics. D) a branch of physics that deals with the curvature of spacetime. E) a branch of physics that deals with the properties of gases.