FarleyPhysics.com

1. Finish October Sky

2. Return Test  (page 6 in notes)

3. Projectile Motion (page 7 in notes)

Today you will study projectile motion. At the end of the day you should know the angle to launch a projectile if you want it to go the furthest, the angle if you want it to go the highest, and what air resistance will do to the distance it goes.

Use the following simulation to answer the questions.

1. Find the angle that a projectile should be launched for it to go the longest distance away from where it was launched.

In your notes: Draw a picture of the height vs. distance graph with the furthest distance.  Label the drawing with your answer or copy the question.

2. Find the angle that makes the projectile go the highest.

In your notes: Draw a picture of height vs. distance for this and title the drawing with the question and answer.

3. Add air resistance and explain what happens to the distance a projectile can go with air resistance vs. without air resistance.

In your notes: Draw a picture showing both and label the path with air resistance and without.  Title the drawing “Projectile with and without air resistance”

4. Turn air resistance off and change the mass. What happens to the distance a projectile goes as you increase mass?

In your notes: No need to draw this one, just state the answer with the question included.

Go to this link and try to find the velocity that makes the cannon orbit the earth in a perfect circle.  It will hit the top of the mountain when it comes back around.

In your notes: Draw three pictures:  One where the cannonball hits the ground, one where the cannonball orbits in a perfect circle, and one where the cannonball leaves the earth for good (escape velocity).  Label each scenario and explain in one or two sentences what is happening in the picture.

Vector Questions (for each problem, draw the triangle and label the sides and hypotenus)

 

Page 5 in notes

 

If an airplane travels through the air at 30 m/s heading South into a wind heading 10 m/s North, what is the velocity of the plane relative to the ground?

 

 

 

If an airplane travels through the air at 50 m/s heading South with a wind heading 10 m/s South as a tailwind, what is the velocity of the plane relative to the ground?

 

 

 

If an airplane travels through the air at 30 m/s heading South with a wind heading 30 m/s East, what is the velocity of the plane relative to the ground?

 

 

 

If an airplane travels through the air at 50 m/s heading South into a headwind heading 50 m/s North what is the velocity of the plane relative to the ground?

 

 

 

If a boat travels through the water at 4 m/s heading across a river that is flowing at 3 m/s, what is the velocity of the boat?

 

 

 

If you walk 30 m north and then walk 40 meters west, what is your displacement?

 

 

 

If you move 40 m north and then move 30 m west, what is your displacement?

 

 

 

If you drive a car 100 miles north and then turn east and drive for another 100 miles, what distance are you from where you started? In what direction are you with respect to where you started?

 

 

If a speedboat travels through the water at 36 m/s toward the East and the current is moving at 27 m/s North, what is the resultant velocity of the speedboat?

 

 

 

 

 

 

Vectors vs. scalars

1. What are they and some examples

displacement vs. distance
velocity vs. speed
acceleration is a vector quantity
Force is a vector quantity

2. Adding parallel vectors

3. Adding perpendicular vectors:  Even Sided and 3-4-5 triangle

Problems: Page 41 Plug and chug 19, 20, 21.  Page 4

For today’s assignment, find Firefox in the Applications folder and use it.

riverboat questions.odt.

1.Run the simulation here and answer the questions the best you can.

Hint for #1: change the river speed and see how long it takes to cross the river.  Then change it again and see if the time changes.

Hint for #2: Change boat speed and river speed and see which one effects the time to cross the most.

Hint for #3: Change the direction of the boat and see which direction gets the boat across the river the quickest.

Hint for #4: use time to cross = distance/boat speed and distance = current speed * time to cross.

Hint for #6: find out how long it takes until the current takes you over the falls (t= d/s or time to live = distance to waterfall/ speed of river), then use that time to find the speed needed to cross the river (s = d/t).

2. Put the questions as Page 1 in your notebook and start a new Table of Contents.

Homework: Read pages 28-32 in the book and answer 1-6 on page 40.  Be sure to write out the questions.  This will be page 2 named: Vector Reading Questions.