Astro 7N psu Exam 1 Unit 1 & 2
Newton's first law of gravity - correct answer-an object at rest or in motion in a straight line at
a constant speed will remain in that state unless acted upon by a force
Newton's second law - correct answer-force=mass x acceleration
-if the same amount of force is applied to two objects the object with a smaller mass will
move faster
Newton's third law - correct answer-every action has an equal and opposite reaction
Surface gravity on a planet - correct answer-g= mass/radius^2
more mass = stronger surface gravity - correct answer-if the mass of a planet were twice that
of another but they had the same radius the gravity felt on the surface of the more massive
one would be twice as strong
Newton's Universal law of gravitation - correct answer--force of attraction that exists between
all objects in the universe
-force= (mass of object 1) x (mass of object 2)/ distance between the objects ^2
What causes day and night? - correct answer-rotation of the earth on its axis
How does the sun appear to move in the sky in the course of a day? - correct answer-east to
west, because of earth's rotation
the stars and the planets move in the same way from our point of view because of earths
rotation
what happens to the earth in one year? - correct answer-it orbits the sun once
why do we have seasons? - correct answer-The tilt of the Earth's axis which is about 23
degrees
How is the Earth's axis tilted when we have summer in the Northern hemisphere? - correct
answer-with the North Pole towards the sun
what season is it in the Southern Hemisphere when it is summer in the northern
hemisphere? - correct answer-winter
winter begins on - correct answer-dec.21, in the northern hemisphere the nights are longer
than the days
spring begins on - correct answer-march 21, days and nights have equal length
summer begins on - correct answer-June 21, days are longer than the nights
Newton's first law of gravity - correct answer-an object at rest or in motion in a straight line at
a constant speed will remain in that state unless acted upon by a force
Newton's second law - correct answer-force=mass x acceleration
-if the same amount of force is applied to two objects the object with a smaller mass will
move faster
Newton's third law - correct answer-every action has an equal and opposite reaction
Surface gravity on a planet - correct answer-g= mass/radius^2
more mass = stronger surface gravity - correct answer-if the mass of a planet were twice that
of another but they had the same radius the gravity felt on the surface of the more massive
one would be twice as strong
Newton's Universal law of gravitation - correct answer--force of attraction that exists between
all objects in the universe
-force= (mass of object 1) x (mass of object 2)/ distance between the objects ^2
What causes day and night? - correct answer-rotation of the earth on its axis
How does the sun appear to move in the sky in the course of a day? - correct answer-east to
west, because of earth's rotation
the stars and the planets move in the same way from our point of view because of earths
rotation
what happens to the earth in one year? - correct answer-it orbits the sun once
why do we have seasons? - correct answer-The tilt of the Earth's axis which is about 23
degrees
How is the Earth's axis tilted when we have summer in the Northern hemisphere? - correct
answer-with the North Pole towards the sun
what season is it in the Southern Hemisphere when it is summer in the northern
hemisphere? - correct answer-winter
winter begins on - correct answer-dec.21, in the northern hemisphere the nights are longer
than the days
spring begins on - correct answer-march 21, days and nights have equal length
summer begins on - correct answer-June 21, days are longer than the nights
