The Schwarzchild radius of a black hole is that radial distance from the center of a sphere within which not even light can escape. It was first discovered mathematically by Schwarzchild in 1916 after Einstein published his general relativity theory.
It can be calculated from a star's mass M as: R = 2GM/c2. If the mass of star G is twice as much as the mass of star H, the average density of star G compared to star H will be A) twice as much.
B) half as much.
C) four times as much.
D) one-fourth as much.
E) eight times as much.
Question 2The Hawaiian Islands were formed when
A) oceanic crust sank below continental crust at a tectonic plate boundary
B) volcanic material flowed out from the interior at a hot spot beneath the Pacific Ocean
C) molten lava oozed out between two tectonic plates that were slowly moving apart
D) dense material sank while lighter material rose to the surface during the early geological history
Question 3A lens is coated with material of index of refraction 1.38. What thickness of coating should be used to give maximum transmission at a wavelength of 0.53 m?
What will be an ideal response?
Question 4A very long solenoid has 1.0 106 turns per meter and a cross-sectional area of 2.0 106 m2. A short, secondary coil with 1.0 103 turns is wound over the solenoid's midpoint.
What emf is induced in the secondary coil if the current in the solenoid is changing at a rate of 4.0 A/s? A) 1.0 V
B) 2.7 V
C) 1.6 V
D) 0.52 V
E) 4.4 V
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