Astro 7N Unit 1 UPDATED Exam
Questions and CORRECT Answers
Newton's First Law - 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 - The acceleration of a body due to a force
will be in the same direction as the force, with a magnitude inversely proportional to its mass (F
= ma)
Newton's Third Law - CORRECT ANSWER - For every action, there is an equal and
opposite reaction (Sun exerts force on planets, and they orbit it — the planets exert equal force
on Sun, but it only moves slightly because of its very large mass relative to the planets.)
Strength of gravity on the surface of a planet (equation) - CORRECT ANSWER -g=M/
R^2
M: mass
R: radius
Newton's Universal Law of Gravitation - CORRECT ANSWER - Force of gravity is
proportional to (M1 x M2) / d^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 the day? - CORRECT
ANSWER - East to west (because of Earth's rotation)
What happens to the Earth in one year? - CORRECT ANSWER - It completes on
revolution about the Sun
, Why do we have seasons? - CORRECT ANSWER - The tilt of the Earth's axis of rotation,
with respect to the plane of it's orbit about the Sun (23 degrees)
How is the Earth's axis tilted when we have summer in the Northern hemisphere? - CORRECT
ANSWER - With the North pole toward the Sun
What season is it in the Southern hemisphere when it is summer in the Northern hemisphere? -
CORRECT ANSWER - Winter
When does winter begin in the Northern hemisphere? - CORRECT ANSWER - Dec. 21
(nights are longer than days)
When does spring begin in the Northern hemisphere? - CORRECT ANSWER - March 21
(days and nights have equal length)
When does summer begin in the Northern hemisphere? - CORRECT ANSWER - June 21
(days are longer than nights in the North)
When does fall begin in the Northern hemisphere? - CORRECT ANSWER - Sept. 21
(days and nights have equal length)
What happens to the moon in 1 month? - CORRECT ANSWER - It moves once around
the Earth
What causes the phases of the Moon? - CORRECT ANSWER - Sun is lighting up
different fractions of the part of the Moon seen from Earth
What is the order of the phases of the Moon - CORRECT ANSWER - New moon, waxing
crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter, waning
crescent, new moon
Questions and CORRECT Answers
Newton's First Law - 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 - The acceleration of a body due to a force
will be in the same direction as the force, with a magnitude inversely proportional to its mass (F
= ma)
Newton's Third Law - CORRECT ANSWER - For every action, there is an equal and
opposite reaction (Sun exerts force on planets, and they orbit it — the planets exert equal force
on Sun, but it only moves slightly because of its very large mass relative to the planets.)
Strength of gravity on the surface of a planet (equation) - CORRECT ANSWER -g=M/
R^2
M: mass
R: radius
Newton's Universal Law of Gravitation - CORRECT ANSWER - Force of gravity is
proportional to (M1 x M2) / d^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 the day? - CORRECT
ANSWER - East to west (because of Earth's rotation)
What happens to the Earth in one year? - CORRECT ANSWER - It completes on
revolution about the Sun
, Why do we have seasons? - CORRECT ANSWER - The tilt of the Earth's axis of rotation,
with respect to the plane of it's orbit about the Sun (23 degrees)
How is the Earth's axis tilted when we have summer in the Northern hemisphere? - CORRECT
ANSWER - With the North pole toward the Sun
What season is it in the Southern hemisphere when it is summer in the Northern hemisphere? -
CORRECT ANSWER - Winter
When does winter begin in the Northern hemisphere? - CORRECT ANSWER - Dec. 21
(nights are longer than days)
When does spring begin in the Northern hemisphere? - CORRECT ANSWER - March 21
(days and nights have equal length)
When does summer begin in the Northern hemisphere? - CORRECT ANSWER - June 21
(days are longer than nights in the North)
When does fall begin in the Northern hemisphere? - CORRECT ANSWER - Sept. 21
(days and nights have equal length)
What happens to the moon in 1 month? - CORRECT ANSWER - It moves once around
the Earth
What causes the phases of the Moon? - CORRECT ANSWER - Sun is lighting up
different fractions of the part of the Moon seen from Earth
What is the order of the phases of the Moon - CORRECT ANSWER - New moon, waxing
crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter, waning
crescent, new moon
