A short recording since most of the class was taken up with lab.
Tuesday, February 28, 2017
Monday, February 27, 2017
2/27 Physics Class and homework due 3/13
Hi folks,
First off NO CLASS NEXT WEEK!!! Next week is Spring Break so there will be no class.
To start with today, we spent a bit of time working more with those pesky energy formulas.
Then, I had the students spend time figuring out everything they possibly could using Hot Wheels stuff. On their own, they set up experiments and took measurements in order to try to find potential energy, kinetic energy, velocity, impulse, energy efficiency and more. It does an old physics teacher's heart good to see a batch of students debating the appropriate approaches to creating and solving practical physics problems.
For homework this week, please write up your methods and results.
In other words,
a. What did you try to find,
b. How did you go about trying to find it.
c. What was your raw data (times, distances etc).
d. What were your calculations.
e. What are your conclusions.
f. Do you feel you conclusions are valid or could there be some errors in your procedure?
g. What would you do differently, if anything, if you were to try to find the same data again?
Also, after playing with the materials, did any activities occur to you that would be fun/interesting/educational for kids aged 8 - 14? Try to come up with at least two activities.
First off NO CLASS NEXT WEEK!!! Next week is Spring Break so there will be no class.
To start with today, we spent a bit of time working more with those pesky energy formulas.
Then, I had the students spend time figuring out everything they possibly could using Hot Wheels stuff. On their own, they set up experiments and took measurements in order to try to find potential energy, kinetic energy, velocity, impulse, energy efficiency and more. It does an old physics teacher's heart good to see a batch of students debating the appropriate approaches to creating and solving practical physics problems.
For homework this week, please write up your methods and results.
In other words,
a. What did you try to find,
b. How did you go about trying to find it.
c. What was your raw data (times, distances etc).
d. What were your calculations.
e. What are your conclusions.
f. Do you feel you conclusions are valid or could there be some errors in your procedure?
g. What would you do differently, if anything, if you were to try to find the same data again?
Also, after playing with the materials, did any activities occur to you that would be fun/interesting/educational for kids aged 8 - 14? Try to come up with at least two activities.
Thursday, February 23, 2017
Chemistry Next Year?
Hi folks,
It looks like things may be shaping up for a High School Level Chemistry course on Wednesday mornings. We could do it 10 - 12, 10:30 to 12:30 or start earlier. Would any of those times work for you? Please don't hesitate to mention this to any other folks who you feel may be interested.
Best,
Jim Mueller
It looks like things may be shaping up for a High School Level Chemistry course on Wednesday mornings. We could do it 10 - 12, 10:30 to 12:30 or start earlier. Would any of those times work for you? Please don't hesitate to mention this to any other folks who you feel may be interested.
Best,
Jim Mueller
Tuesday, February 21, 2017
Monday, February 20, 2017
2/20 Physics Class and homework due 2/27
Hi folks,
Today we took the time to really work with the three major energy formulas and tackle several problems.
For homework this week answer the following problems. I've included answers to the math problems below. These will be quizzed on next week so please take the time to really get to know these.
1. Assume the following to answer the questions below:
Mass of ball = .05 kg
Height of ramp = .032 m
Ave. velocity of ball on ramp = .4 m/s
Distance ball rolled after getting off ramp = 3 m
a. What makes the ball stop after getting off the ramp?
b. What was the velocity of the ball at the very bottom of the ramp? (Careful here!)
c. What was the gPE of the ball at the top of the ramp?
d. What was the gPE of the ball at the bottom of the ramp?
e. What happened to the gPE?
f. What was the KE of the ball at the bottom of the ramp?
g. Where did the energy of the system originally come from?
h. What amount of work did friction do to the ball after it got off the ramp to the point where the ball stopped rolling?
i. Where did the energy go that caused the ball to stop?
j. What is the friction force of the carpet on the ball?
2. Thinking about the energy formulas, tell me if it make sense to have a heavy vehicle or a light vehicle as far as gPE goes.
3. If you created a balloon powered car, would you want it to be heavy? Why or why not?
4. If you and a friend were on identical sleds and your friend weighs twice as much as you do, which of you would go farther? Which of you would have more velocity? Describe this in relation to momentum and describe this in relation to energy.
Use these formulas to solve the following Olympic energy problems. Answers below.
gPE = MgH
KE = ½ MV^2 (^2 means squared)
W = FD
5. A ski jumper who has a mass of 80 kg stands at the top of a ski jump that is 15m tall.
a. What is his potential energy?
b. If there's no friction, what would his speed be as he launches from the jump?
c. If his speed is 13 m/s, what is the energy efficiency of the ramp?
d. What work did friction do on our ski hero?
e. What was the average force of friction between the ramp and his skis if he travels
75 m down the ramp
6. a. If the Irish bob sled with a mass of 320 kg reaches a top speed of 48 m/s, what was the least amount of energy the bob sled started with?
b. What was the lowest height the bob sled started at?
c. If the stopping area of the track is 30m long, what work will friction do on our Irish bob sledders by the time the team comes to a complete rest at the bottom?
d. If the height of the track was really 200 m, what was the energy efficiency of the bob sled?
Answers to math problems
1. b. .8 m/s (twice the average speed)
c. gPE = .05 x 10 x .032
gPE = .016 J
d. 0 J
f. KE = 1/2 .05kg x (.8m/s)^2
KE = .016 J
h. Work due to friction = .016J
j. .016 = F x 3
. 0053 N = F
5. a. gPE = Mgh
80 kg x 15 m x 10 m/s^2 = 12,000J
b. KE = ½ MV^2
12,000 J = ½ 80 kg x v^2
v = 17.3 m/s
c. KE = ½ 80kg x (13m/s)^2
KE = 6760 J
Work out/ Work in x 100
6760/12000 x 100 = 56% Efficient
d. 12,000J - 6760J = 5240 J amount of energy friction stole
e. W = FD
5240J = F x 75m
F = 69.9 N amount of force friction applied to skier
6. a. KE = ½ MV^2
KE = ½ 320kg (48 m/s)^2
KE = 368,640 J
b. gPE = MgH
368,640 = 320kg x 10m/s^2 x H
H = 115.2 m (That's some ramp!)
c. W = FD
368,640 J = F x 30 m
F = 12,288 N (A typical car braking force is 15,000N)
d. gPE = MgH
gPE = 320 kg x 10 m/s^2 x 200 m
gPE = 640,000 J That's the maximum amount of energy. Since their energy was 368,640 J their energy efficiency was…
Work out / Work in x 100
368,640/ 640,000 x 100 = 58%
Today we took the time to really work with the three major energy formulas and tackle several problems.
For homework this week answer the following problems. I've included answers to the math problems below. These will be quizzed on next week so please take the time to really get to know these.
1. Assume the following to answer the questions below:
Mass of ball = .05 kg
Height of ramp = .032 m
Ave. velocity of ball on ramp = .4 m/s
Distance ball rolled after getting off ramp = 3 m
a. What makes the ball stop after getting off the ramp?
b. What was the velocity of the ball at the very bottom of the ramp? (Careful here!)
c. What was the gPE of the ball at the top of the ramp?
d. What was the gPE of the ball at the bottom of the ramp?
e. What happened to the gPE?
f. What was the KE of the ball at the bottom of the ramp?
g. Where did the energy of the system originally come from?
h. What amount of work did friction do to the ball after it got off the ramp to the point where the ball stopped rolling?
i. Where did the energy go that caused the ball to stop?
j. What is the friction force of the carpet on the ball?
2. Thinking about the energy formulas, tell me if it make sense to have a heavy vehicle or a light vehicle as far as gPE goes.
3. If you created a balloon powered car, would you want it to be heavy? Why or why not?
4. If you and a friend were on identical sleds and your friend weighs twice as much as you do, which of you would go farther? Which of you would have more velocity? Describe this in relation to momentum and describe this in relation to energy.
Use these formulas to solve the following Olympic energy problems. Answers below.
gPE = MgH
KE = ½ MV^2 (^2 means squared)
W = FD
5. A ski jumper who has a mass of 80 kg stands at the top of a ski jump that is 15m tall.
a. What is his potential energy?
b. If there's no friction, what would his speed be as he launches from the jump?
c. If his speed is 13 m/s, what is the energy efficiency of the ramp?
d. What work did friction do on our ski hero?
e. What was the average force of friction between the ramp and his skis if he travels
75 m down the ramp
6. a. If the Irish bob sled with a mass of 320 kg reaches a top speed of 48 m/s, what was the least amount of energy the bob sled started with?
b. What was the lowest height the bob sled started at?
c. If the stopping area of the track is 30m long, what work will friction do on our Irish bob sledders by the time the team comes to a complete rest at the bottom?
d. If the height of the track was really 200 m, what was the energy efficiency of the bob sled?
Answers to math problems
1. b. .8 m/s (twice the average speed)
c. gPE = .05 x 10 x .032
gPE = .016 J
d. 0 J
f. KE = 1/2 .05kg x (.8m/s)^2
KE = .016 J
h. Work due to friction = .016J
j. .016 = F x 3
. 0053 N = F
5. a. gPE = Mgh
80 kg x 15 m x 10 m/s^2 = 12,000J
b. KE = ½ MV^2
12,000 J = ½ 80 kg x v^2
v = 17.3 m/s
c. KE = ½ 80kg x (13m/s)^2
KE = 6760 J
Work out/ Work in x 100
6760/12000 x 100 = 56% Efficient
d. 12,000J - 6760J = 5240 J amount of energy friction stole
e. W = FD
5240J = F x 75m
F = 69.9 N amount of force friction applied to skier
6. a. KE = ½ MV^2
KE = ½ 320kg (48 m/s)^2
KE = 368,640 J
b. gPE = MgH
368,640 = 320kg x 10m/s^2 x H
H = 115.2 m (That's some ramp!)
c. W = FD
368,640 J = F x 30 m
F = 12,288 N (A typical car braking force is 15,000N)
d. gPE = MgH
gPE = 320 kg x 10 m/s^2 x 200 m
gPE = 640,000 J That's the maximum amount of energy. Since their energy was 368,640 J their energy efficiency was…
Work out / Work in x 100
368,640/ 640,000 x 100 = 58%
Friday, February 17, 2017
Inquiry for next year Chemistry class
Hi folks,
Just checking in to see who may be interested in continuing science classes next year. My thought it to have a Chemistry class on Tuesdays. At the moment, it could be in the morning or afternoon.
Please let me know if you are interested and if so, which time would be better for you.
Also, please feel free to pass this information on to anyone you may know who would be interested.
I've included a description of the class below.
High School Level Chemistry
An enjoyable, hands-on and thorough approach to basic chemistry. The class will be a combination of hands-on lab work as well as lecture. We will cover the periodic table, stoichiometry, energy in chemistry, acids and bases, redox reactions and much more. A good working knowledge of algebra 1 is recommended.
Just checking in to see who may be interested in continuing science classes next year. My thought it to have a Chemistry class on Tuesdays. At the moment, it could be in the morning or afternoon.
Please let me know if you are interested and if so, which time would be better for you.
Also, please feel free to pass this information on to anyone you may know who would be interested.
I've included a description of the class below.
High School Level Chemistry
An enjoyable, hands-on and thorough approach to basic chemistry. The class will be a combination of hands-on lab work as well as lecture. We will cover the periodic table, stoichiometry, energy in chemistry, acids and bases, redox reactions and much more. A good working knowledge of algebra 1 is recommended.
Tuesday, February 14, 2017
Monday, February 13, 2017
2/13 Physics Class and homework due 2/20
Hi folks,
Today we got into quite a bit of the nitty gritty of energy by beginning to explore the different energy formula and how they interrelate to one another. Next week we will take some more time to really focus on these kinds of problems in class.
For homework this week:
Finish your lab calculations if you haven't already done so in class.
Read the Potential and Kinetic energy chapter in the eBook.
Do all the questions at the end.
Also, answer the following questions about today's lab.
1. What did you do to find the work in?
2. What did you do to find the work out?
3. What was having work done on it?
4. What would be considered the "load" in this lab?
5. In a perfect world, how should the energy of the ball at the bottom of the ramp, compare to the energy at the top of the ramp?
6. Since we know that energy can neither be created or destroyed, where did that energy go?
Also, find four physics errors using four different movies, cartoons, books or a video games. In other words, try to find four things that just go against the laws of physics and describe why and how they are breaking those rules. Feel free to use screen shots if you wish. Have fun with this!
Today we got into quite a bit of the nitty gritty of energy by beginning to explore the different energy formula and how they interrelate to one another. Next week we will take some more time to really focus on these kinds of problems in class.
For homework this week:
Finish your lab calculations if you haven't already done so in class.
Read the Potential and Kinetic energy chapter in the eBook.
Do all the questions at the end.
Also, answer the following questions about today's lab.
1. What did you do to find the work in?
2. What did you do to find the work out?
3. What was having work done on it?
4. What would be considered the "load" in this lab?
5. In a perfect world, how should the energy of the ball at the bottom of the ramp, compare to the energy at the top of the ramp?
6. Since we know that energy can neither be created or destroyed, where did that energy go?
Also, find four physics errors using four different movies, cartoons, books or a video games. In other words, try to find four things that just go against the laws of physics and describe why and how they are breaking those rules. Feel free to use screen shots if you wish. Have fun with this!
Tuesday, February 7, 2017
Monday, February 6, 2017
Physics Homework due 2/13
Hi folks,
Today we did a a little more with the idea of simple machines and work as we investigated levers.
For homework this week:
Review questions page 120 #'s 14 - 20
Answer sheet is included.
Plug and Chug page 120 #'s 4 - 9
Wednesday, February 1, 2017
Wrong book for the homework
Hi folks,
Sorry I included the wrong version of the book for the homework. Here is the right version.
Sorry I included the wrong version of the book for the homework. Here is the right version.
Subscribe to:
Posts (Atom)