Cosmology and Thermodynamics Quiz

Redshift in their spectra indicates that stars are moving away from Earth.

It led to the realization that the universe is expanding.

Friedmann assumed that the universe looks the same in all directions, indicating uniformity.

<p>They found unexpected excess noise that didn’t seem to come from a specific direction.</p> Signup and view all the answers

<p>They initially thought it might be due to bird droppings in their detector.</p> Signup and view all the answers

<p>The noise remained consistent regardless of direction and time, suggesting it was not from local sources.</p> Signup and view all the answers

<p>It implies that there is no special center in the universe.</p> Signup and view all the answers

<p>Their findings contributed to the confirmation of the Big Bang theory through the detection of cosmic microwave background radiation.</p> Signup and view all the answers

<p>They concluded that its source was cosmic in origin, not local.</p> Signup and view all the answers

<p>It states that if two systems are in thermal equilibrium with a third, they are in equilibrium with each other.</p> Signup and view all the answers

<p>Energy cannot be created or destroyed, only transformed or transferred.</p> Signup and view all the answers

<p>It states that the total entropy of an isolated system always increases over time.</p> Signup and view all the answers

<p>The entropy approaches zero.</p> Signup and view all the answers

<p>It is a remnant of the early Big Bang and provides strong evidence supporting the Big Bang theory.</p> Signup and view all the answers

<p>Thermal equilibrium occurs when two systems have no net heat exchange, implying they are at the same temperature.</p> Signup and view all the answers

<p>A black hole refers to a region in space with a gravitational pull so strong that not even light can escape.</p> Signup and view all the answers

<p>Black hole.</p> Signup and view all the answers

<p>Hydrogen.</p> Signup and view all the answers

<p>They collide more frequently and at greater speeds, heating up.</p> Signup and view all the answers

<p>They coalesce to form helium.</p> Signup and view all the answers

<p>More massive stars use up their fuel faster, leading to a shorter lifespan.</p> Signup and view all the answers

<p>The Pauli exclusion principle.</p> Signup and view all the answers

<p>He calculated the maximum size a star could be to prevent collapse under gravity.</p> Signup and view all the answers

<p>The balance between pressure from nuclear reactions and gravitational attraction.</p> Signup and view all the answers

<p>Einstein's Equivalence Principle allows for the cancelation of gravity effects in free-fall, enabling the application of special relativity to compare time flows between falling clocks.</p> Signup and view all the answers

<p>The Doppler effect causes the ceiling clock, moving toward the floor clock, to emit light pulses that arrive more frequently, indicating that time flows faster at the ceiling than at the floor.</p> Signup and view all the answers

<p>Both clocks are in free fall, which means they are nearly stationary relative to their initial positions during that short time interval.</p> Signup and view all the answers

<p>The ceiling clock's faster fall leads to a higher frequency of light pulses received by the floor clock, demonstrating that time flows faster at the ceiling than at the floor.</p> Signup and view all the answers

<p>Dropping the ceiling clock first allows it to fall faster and affect the light pulse frequency received by the floor clock, thereby illustrating how gravity influences time at different heights.</p> Signup and view all the answers

<p>The Chandrasekhar limit is about one and a half times the mass of the sun, beyond which a star cannot support itself against gravity.</p> Signup and view all the answers

<p>A star that exceeds the Chandrasekhar limit is likely to undergo catastrophic gravitational collapse, potentially leading to a supernova or the formation of a neutron star.</p> Signup and view all the answers

<p>A white dwarf maintains its stability through the exclusion principle repulsion among electrons within its material.</p> Signup and view all the answers

<p>A neutron star is supported by the repulsion from neutrons and protons and is much smaller and denser than a white dwarf.</p> Signup and view all the answers

<p>Neutron stars form from the remnants of massive stars that undergo supernova explosions but are above the Chandrasekhar limit.</p> Signup and view all the answers

<p>Massive stars face the challenge of possibly undergoing gravitational collapse unless they can lose enough mass to fall below the Chandrasekhar limit.</p> Signup and view all the answers

<p>The theory of relativity limits the velocities of matter particles in a star to the speed of light, which affects the effectiveness of repulsion from the exclusion principle.</p> Signup and view all the answers

<p>The exclusion principle is significant because it provides the repulsive force that counters gravitational attraction, helping to stabilize stars like white dwarfs.</p> Signup and view all the answers

<p>Observers on the train see the light reaching both ends simultaneously, while the observer on the platform sees the light reaching the back of the train first due to the train's motion.</p> Signup and view all the answers

<p>The speed of light is constant for all observers, leading to varying measurements of time for the same events depending on their relative motion.</p> Signup and view all the answers

<p>Time in a moving frame is calculated using the equation $t' = \gamma(t - \frac{vx}{c^2})$, where $\gamma$ accounts for relativistic effects.</p> Signup and view all the answers

<p>The Lorentz factor, $\gamma = \frac{1}{\sqrt{1 - \frac{v^2}{c^2}}}$, quantifies how much time is dilated or contracted based on the relative speed between observers.</p> Signup and view all the answers

<p>Different states of motion can lead to disagreements about the simultaneity of events, meaning events that are simultaneous in one frame may not be simultaneous in another.</p> Signup and view all the answers

<p>The thought experiment illustrates the relativity of simultaneity, showing how two observers moving relative to each other can disagree on the timing of events.</p> Signup and view all the answers

<p>A reference frame is a perspective from which measurements are made, and it is important because it determines how observers perceive events and their timing.</p> Signup and view all the answers

<p>The times differ because the observer on the platform measures different distances for the light traveling towards the backs and fronts of the train due to the train's forward motion.</p> Signup and view all the answers