Locked in set paper 1 Flashcards
(20 cards)
How does a Maxwell-Boltzman distribution change for a higher temperature?
sharper peak and more to the right
What order are the speeds in on the Maxwell-Boltzman distribution?
- Most probable
- Mean speed
- Root mean squared speed
What is Charles law?
Volume is proportional to absolute temperature
What is Boyles law?
Pressure inversely proportional to its volume
Newtons 1st law?
An object will stay at rest or constant velocity unless a resultant force acts on an object
Newtons 2nd law?
Rate of change of momentum is proportional to the net force on the object
Newtons 3rd law?
Each force has an equal, opposite reaction force
What is the equation for tourque?
Average force x distance between forces
What are the units in dsin(x)=n x wavelength
d = slit seperation
sin(x) = angle between central and n maxima
n = difference in maxima
wavelength = wavelength
What does homogeneous mean in terms of the cosmological principle?
The density is the same at all points
What does isotropic mean in terms of the cosmological principle?
It looks the same in all places
What is the relationship between recesional velocity and distance?
They are proportional
What is CMBR?
Gamma radiation from the big bang but as the universe has been expanding the wavelengths have been stretched so it is now in the microwave region
What does the spectrum of background radiation correspond too?
2.7K
What was the order of the big bang?
10^-43 - infinitely dense and hot
10^-43 to 10^-4 - Only one force but as universe expands and cools it splits into gravity, strong nuclear, weak nuclear and electrostatic forces
Sea of quarks, anti quarks, leptons and photons
Too much energy for quarks to form protons and neutrons
10^-4 - Cooled enough for protons and neutrons to be formed from quarks
Matter and antimatter anhialate each other leaving photons in the form of gamma radiation
100s - Cooled enough for helium to fuse
300,000 years - Cooled enough for electrons to combine with helium and hydrogen to create atoms
What was evidence for dark matter?
Some galaxies are moving quicker than their mass should suggest so for newtons laws to work there must be some extra mass we cannot see
How much dark matter is there?
5 times normal matter
25% of universe
What evidence is there for dark energy?
Expansion of the universe is speeding up
What could be dark matter?
MACHOS - Massive Compact Halo Objects
WIMPs - Weakly Interacting Massive Particles
What do colder and hotter stars look like on a power output to wavelength graph
Hotter has a sharper peak and has a shorter peak wavelength
Colder has a flatter peak and a longer peak wavelength
