Sir Isaac Newton's Laws
According to Newton's first law of gravity, how is every single object in the Universe attracted to every other object?
Every object in the Universe is attracted to every other object by a gravitational force.
Based on the text's definitions, which term describes the baseline "amount of matter in an object"?
Mass
What is the full name of the standard scientific unit used to measure all forces?
The Newton.
Which celestial body has a gravitational force of attraction that "holds the Solar System together"
The Sun (or the Sun's gravitational force).
Why do un-supported objects, such as falling raindrops, move downwards towards the ground?
Because the Earth's gravitational force attracts them downwards toward the centre of the Earth.
According to Newton's second law of gravity, what physical property of the objects determines the size of their gravitational attraction?
The masses of the objects.
Based on the text's definitions, what causes an object to experience a specific "weight"?
The force of gravity acting on the object.
What is the correct, single-letter uppercase symbol used to represent the unit of a newton?
N
How does the total size and force of gravity on the Moon compare to the force of gravity experienced on Earth?
It is only about one-sixth of the force of gravity on Earth.
Large macro-structures in space don't drift apart because of gravity. According to the text's callouts, what does gravity hold together?
Galaxies
According to Newton's third law of gravity, what spatial factor determines how strong or weak the gravitational force between two objects will be?
How close together the objects are.
If an object travels to a completely different part of the Universe, what happens to its total mass?
It does not change (it stays exactly the same no matter where it is in the Universe).
State the correct lowercase symbols that the text uses to represent the mass units grams, kilograms, and tonnes.
Grams is 'g', kilograms is 'kg', and tonnes is 't'.
Why is the force of gravity structurally less strong on the peak of Mount Everest than it is at sea level?
Because it is further away from the centre of the Earth.
Fill in the missing word: The further away we get from Earth, the _________ the force of gravity is.
Smaller
If an object remains at a constant distance from a planet but its total mass is doubled, deduce what will happen to the size of the gravitational force.
The size of the force of attraction will increase.
A person travels from Earth to the Moon. Explain qualitatively what happens to their weight and why, based on the text's sentence relationships
Their weight will decrease because the gravitational force acting on them on the Moon is weaker.
What is the text's rule for writing the specific lowercase symbols for the three distinct mass units mentioned in the text?
Kilogram (kg): The symbol for kilogram is kg. It is always written in lowercase and should not be contracted.
Compare the force of gravity on Jupiter to the force of gravity on Earth, and state the explicit physical reason given for this difference.
The force of gravity on Jupiter is much larger than on Earth because Jupiter is much more massive than the Earth.
If a planet in our Solar System slows down and does not move fast enough in its orbit, what will the Sun's gravity do to it?
Gravity would pull the slower-moving planet directly into the Sun.
Imagine gravity was suddenly switched off across the entire Universe. Describe what would happen to moving planets, moons, and satellites.
They would stop orbiting and continue moving out into outer space in a straight-line path.
Contrast mass and weight using the text definitions to explain which one is an unchanging property of an object and which one can vary.
Mass is the amount of matter in an object and never changes regardless of location. Weight is a force due to gravity, so it changes if the gravitational force changes.
Why is weight measured in the exact same unit used to measure all other forces (newtons) rather than in kilograms, according to the text?
Because weight is defined as a force (specifically, the force of gravity acting on an object), and the unit used to measure all forces is the Newton.
Explain how the physical size and mass of the Moon directly affects the strength of the gravitational force on its surface compared to Earth.
The force of gravity on the Moon is much weaker because the Moon is much smaller than the Earth.
Explain why distant planets further away from the Sun are able to orbit much more slowly than planets that are close to the Sun.
Because the force of gravity is less strong further away from the Sun, meaning less orbital speed is required to keep an object from falling into it.