Numbers for Exam One

Remove["Global`*"]

Numbers for Problem 2

256^(1/3)

N[%]

Problem 3: Turning peak wavelength into temperature

0.29/(2 Pi)

% 10^7

Problem 3: Check temperature against the paper’s value kT=57 eV [Nature 379(1996)233]

57/QuantityMagnitude[UnitConvert[Quantity["BoltzmannConstant"],"eV/K"]]

Problem 3: Calculate radius and luminosity of neutron star...

R=11 1.4^(1/3);
σ=QuantityMagnitude[UnitConvert[Quantity["StefanBoltzmannConstant"],"erg/(sec cm^2 K^4)"]];
L=N[4 Pi (12 10^5)^2σ(5 10^5)^4]

L/QuantityMagnitude[UnitConvert[Quantity["SolarLuminosity"],"erg/s"]]

... and use flux (1.5E-11) and distance (100 pc) from paper to check the answer

d=100QuantityMagnitude[UnitConvert[Quantity["Parsecs"],"cm"]];
N[L/(4 Pi d^2)]

Temperature scale for Problem 4

TE[BV_]=8540/(BV+0.865);

TE[{0,0.4,0.8,1.2}]

Age estimate for Problem 4

N[(5770/6250)^(16/3)]