Space and relativity

Cards (16)

What is a light year?
The distance travelled by light in one year
How is a light year defined?
Distance travelled by electromagnetic wave in a year
How can distances in the sky be measured using parallax?
By measuring angles at different times
What is redshift?
Apparent increase in wavelength of light
What does redshift from distant galaxies suggest?
Distant galaxies are moving away from us
What does a greater redshift indicate about a galaxy?
The galaxy is moving away faster
What theory does the redshift of distant galaxies support?
The Big Bang Theory
What is Hubble’s Law?
Recessional velocity is proportional to distance
What relationship is used to calculate the proportional change in wavelength?
$\frac{\Delta \lambda}{\lambda} =$ $\frac{v}{c}$
What does CMBR stand for?
Cosmic Microwave Background Radiation
What does CMBR provide evidence for?
The Big Bang Theory
What was Einstein’s First Postulate for his Theory of Special Relativity?
Physics laws are the same for all observers
Where is CMBR believed to originate from?
Gamma rays from the Big Bang
What happens to the wavelength of radiation from CMBR as the universe expands?
The wavelength has been stretched
What was Einstein’s Second Postulate for his Theory of Special Relativity?
The speed of light is a universal constant
What is time dilation?
Different observers record different event times