## Dynamics End of Unit

Let’s have a test on Dynamics this week. It will be on Thursday. Tonight (Monday) put in some work on that review assignment given in class today.… read more

## Apparent Weight

Assigned in class today: WS1 # 10, 12, WS2 # 5, 6

What you “feel” as your weight is actually the normal force of the surface below you pushing up on you. This can change!

https://www.flippingphysics.com/apparent-weight.html

https://www.youtube.com/watch?v=iQOHRKKNNLQ

Now back to grade 11: see this example of how to solve a “system of masses” problem.… read more

## Friction & Inclines

Problems assigned in class today: Worksheet 1 # 3, 7, 8, 9

I have given a quick overview of friction in class. If the concept confuses you, or you are interested, the following optional videos are suggested. Otherwise, skip them.

https://www.flippingphysics.com/friction-intro.html

https://www.flippingphysics.com/mu-intro.html

https://www.flippingphysics.com/friction-equation.html

https://www.flippingphysics.com/friction-problem.html

The following is **not **optional.… read more

## More Dynamics Basics!

Today’s assigned practice: Dynamics worksheet 1 # 1, 4, 5.

We looked at the 2nd law in class. Now lets briefly review the 3rd law:

https://www.flippingphysics.com/third-law.html

Newton’s second law (F=ma)… let’s extend that to 2-dimensions now!

Force is a vector, so no problem.… read more

## Monday: Dynamics Intro Videos

No work here – just a whole lotta videos. These cover the introductory review of physics 11 concepts regarding force. We will follow with some practice of physics 11 level problems in class tomorrow.

https://www.flippingphysics.com/force.html

https://www.flippingphysics.com/force-of-gravity.html

https://www.flippingphysics.com/weight-not-mass.html

https://www.flippingphysics.com/free-body-diagrams.html

## Practice Test Answers

Your kinematics/vectors unit test is on Monday! Here are the answers to the practice test given on Friday

Multiple Choice

- A
- C
- C
- D
- B
- D
- D
- B
- A
- B

Written

- 7.3 m/s @ 7.4° above the horizontal
- a) 22 m/s b) 24 m
- a) He’s fine.

## Tuesday – 2D Projectiles: Different Heights

First thing, a reminder that the x and y directions are independent of eachother. Motion in the x direction does not cause motion in the y direction – nor vice versa. For proof of this:

https://www.flippingphysics.com/bullet-with-scales.html

Now we consider 2-D projectiles where the start height is different from the end height.… read more

## Lecture: 2-Dimensional Projectiles

First watch this:

https://www.flippingphysics.com/projectile-motion.html

Then watch this, but try to stay one step ahead of him on the problem.

https://www.flippingphysics.com/projectile-motion-problem-part-1-of-2.html

Then watch part 2 of the problem, again staying one step ahead of him on the problem.

https://www.flippingphysics.com/projectile-motion-problem-part-2-of-2.html

One more problem to try.… read more

## Vectors: Components

Add # 5, 7, 9, 12 to “assigned practice”… read more

## Vectors: Tip to Tail

We went over:

* Adding & subtracting vectors by arranging them tip to tail

* Using cosine law to determine the magnitude of the resultant

* Using the sine law to determine the direction of the resultant

* Relative motion can be determined by subtracting the observer’s vector from the subject’s vector

For practice: Do # 8 & 11 from the practice set.… read more