Astro Mid Term Sem. 2 (Book 5/7) Flashcards
(11 cards)
What was Galileo’s thoughts on Gravity?
He believed that all objects fall at the same speed unless air resistance or some other force acts upon them
What is Gravity?
- Gravity is the attractive force that exists between 2 objects
- A property of the space in the presence of an object with mass - the GRAVITATIONAL FIELD
- In Newtonian picture, we live in a 3-dimensional space. The time from space dimensions
What was Einsteins happiest thought?
“I was sitting in a chair in the patent office at Bern when all of a sudden a thought occurred to me: IF A PERSON FALLS FREELY HE WILL NOT FEEL HIS OWN WEIGHT… I was startled. This simple thought made a deep impression on me. It impelled me towards a theory of gravitation.”
- This means that gravity can be cancelled out by acceleration
What is Einstein’s “Equivalence Principle”?
- In any given location, it is impossible to distinguish between the effects of accelerated motion and those of a gravitational field
- Gravity is equivalent to acceleration
How does matter distort spacetime? (use trampoline reference) found in book 5 middle of page 2
- Matter distorts spacetime like weights on a taut rubber sheet
- The greater the mass, the greater the distortion of spacetime
What is Space-Time Curvature?
- Einstein’s theory of General Relativity says that space-time is curved by the presence of a mass
- A mass in space causes a curvature in space fabric
- The curvature then explains the movement of the matter
What is Gravity? (Part 2: specific to spacetime)
- The curvature of the spacetime continuum is produced by the presence of mass
- Massive object distorts spacetime continuum more
Orbits can now be explained in a new way; on object will travel on AS STRAIGHT A PATH AS POSSIBLE through spacetime. TRUE or FALSE?
TRUE
Orbits can now be explained in a new way; on object will travel on AS STRAIGHT A PATH AS POSSIBLE through spacetime. TRUE or FALSE?
TRUE
Orbits can now be explained in a new way; on object will travel on AS STRAIGHT A PATH AS POSSIBLE through spacetime. TRUE or FALSE?
TRUE
Newton’s law predicted that the orbit of Mercury should change. Why is that?
- due to gravitational influence of the planets
- this change was measured in the 1800’s
- BUT Newton’s law could not account for the exact change which was observed
- Einstein knew of this discrepancy and used general relativity to explain it
- Predictions of general relativity matched the observations exactly
