Why is it so difficult to study the center of our galaxy?
a. Light from the center is lost in the glow of emission nebulae in this direction.
b. Interstellar dust blocks almost all light before it reaches Earth.
c. The exact position of the center is not known.
d. The center of the galaxy puts out very little radiation and is too dim to study.
e. The center of the galaxy is too far away for radiation to be detected by telescopes.
Question 2Newton's law of gravitational force states that ____.
a. an object with no force on acting on it continues at rest or moves in uniform motion in a straight line with constant velocity
b. an object with no force on it moves in a straight line with constant acceleration
c. for every action, there is an equal and opposite reaction
d. the force between two objects is directly proportional to the product of their masses and inversely proportional to the distance between them squared
e. an object with a force on it is accelerated in the direction of the force an amount inversely proportional to its mass and directly proportional to the size of the force
Question 3The center of our galaxy contains a very intense source of radio and X-ray radiation named Sgr A. What is it about this source that supports the idea that the radiation comes from a black hole?
a. The radiation is strongly blueshifted, indicating that the object is collapsing.
b. The radiation is strongly redshifted indicating that the object is growing.
c. The radiation is coming from an incredibly small object.
d. Radio waves can only be produced by matter orbiting a black hole.
e. Only radiation from a black hole could penetrate the giant molecular clouds between Sgr A and Earth.
Question 4According to the inverse square law, the force due to gravity between two masses will ____.
a. increase as the distance between the two masses increases
b. decrease as the square of the distance between the two masses increases
c. cause the two masses to move away from each other
d. cause the two masses to move in a straight line
e. cause the two masses to orbit each other
Question 5The center of the Milky Way galaxy is in the direction of the constellation ____.
a. Sagittarius
b. Scorpius
c. Orion
d. Perseus
e. Andromeda
Quick Reply
