Universal Gravitation Part 2

Today we used your graphs from yesterday to come up with the relationships between the masses, distance between the mass centers, and the magnitude of the gravitational force between the masses.



And there weren't many good problems in the textbook, so I wrote some and put them on a little strip of paper: Universal Gravitation Homework. This is suggested homework, which will be assessed Friday.

After all of this, we attempted a demonstration about the idea that gravity isn't really a force, exactly, but the consequences of bending space-time with large masses. This will not be assessed but it is the currently accepted model.

We also talked about gravitational waves, which are super exciting and the first detection of which was only a few years ago. Here is a pretty awesome video from Science Bulletin: Gravity-Making Waves. This was made before the first detection, though.

Universal Gravitation Part 1

This lesson will take two days. We started with a Plickers from last week's suggested homework, then used some fake data to derive the Law of Universal Gravitation (Newtonian gravitation). Here is the activity: Universal Gravitation Pseudo-Lab. Today we got as far as making the graphs; please finish for homework so we can jump into the results tomorrow.

Here are the graphs you need to make and some linearizations to try when you don't get a line:

Orbits

Today we combined universal gravitation and uniform circular motion to find the mass of the sun given the radius and period of the orbit of the earth. Along the way, we basically derived Kepler's 3rd Law.

There is no homework, but you probably picked up your practice test today.

Rotational Motion Test Practice

Answers

Solutions videos:

#2

#3

#4

#6

#8

#9

Universal Gravitation

Today we used some fake data to derive the Law of Universal Gravitation (Newtonian graviation). Here is the activity: Universal Gravitation Pseudo-Lab.

Here is what ended up on the board:



And there weren't many good problems in the textbook, so I wrote some and put them on a little strip of paper: Universal Gravitation Homework.

After all of this, we attempted a demonstration that I've never tried before about the idea that gravity isn't really a force, exactly, but the consequences of bending space-time with large masses. This will not be assessed but it is the currently accepted model.

We also talked about gravitational waves, which are super exciting and the first detection of which was only a few years ago. Here is a pretty awesome video from Science Bulletin: Gravity-Making Waves. This was made before the first detection, though.

Rotational Motion Test Practice

Rotational Motion Test Practice

Answers

Solutions videos:
#1
#2
#3
#4
#6
#7
#8
#9

Remember that any of these numerical problems could be a symbolic problem (no numbers) on the test.

I tried to check everyone's labs today, but if I didn't get yours checked please have it ready on Monday/Tuesday.

Universal Gravitation

Today we used some fake data to derive the Law of Universal Gravitation. Here is the activity: Universal Gravitation Pseudo-Lab.

Here is what ended up on the board:

And there weren't many good problems in the textbook, so I wrote some and put them on a little strip of paper: Universal Gravitation Homework.

Rotational Motion Practice Test

Rotational Motion Test Practice

Answers

Solutions videos:
#1
#2
#3
#4
#6
#7
#8
#9

Remember that any of these numerical problems could be a symbolic problem (no numbers) on the test.

Orbits

Today we combined universal gravitation and uniform circular motion to find the mass of the earth given the radius and period of the orbit of the moon.

There is no homework, but you probably picked up your practice test today. We also have a small vector quiz tomorrow.

Universal Gravitation

Today we used some fake data to derive the Law of Universal Gravitation. It ended up on the board:



Here is the fake data activity: Universal Gravitation Pseudo Lab

Homework was printed out on little strips. Here is an electronic copy: Homework 11/30. Don't forget to do the back.

Wrapping Up the Unit & Practice Exam

First we combined the Law of Universal Gravitation and circular motion to derive an interesting equation relating the radius of an orbit to period (period T = time for one cycle).

Then we talked briefly about tides and passed out the practice exam:

Rotational Motion Test Practice

Answers

Solutions videos:
#1
#2
#3
#4
#6
#7
#8
#9

Tomorrow we will be talking about science classes available for your senior year and the importance of taking a fourth year of science. Your test will be the last hour of your modular day when we get back from Thanksgiving Break, so the first 45 minutes will be work time. There will be no additional homework tonight; I would rather that you focus on the practice exam.

Universal Gravitation

Today we used some fake data to derive the Law of Universal Gravitation. It ended up on the board:

Here is the fake data activity: Universal Gravitation Pseudo Lab

Homework was printed out on little strips. Here is an electronic copy: Homework 11/23. Don't forget to do the back.

Wrapping Up the Unit & Practice Exam

First we combined the Law of Universal Gravitation and circular motion to derive an interesting equation relating the radius of an orbit to period (period T = time for one cycle).

Then we talked briefly about tides and passed out the practice exam:

Chapter 7 Practice Exam

Solutions videos:
#1
#2
#3
#4
#5
#6
#7
#8

Monday will be a review day and Tuesday will be your test. Some people have expressed an interest in taking the test on Monday and having a workday on Tuesday instead due to the sheer number of other tests on Tuesday. That is fine - I will make an alternate version of the test for the early testers.

There will be no additional homework tonight; I would rather that you focus on the practice exam.

Universal Gravitation

Today we used some fake data to derive the Law of Universal Gravitation. It ended up on the board:

Here is the fake data activity: Universal Gravitation Pseudo Lab

Homework was printed out on little strips. Here is an electronic copy: Homework 11/19. Don't forget to do the back.