-Calibrate the length of a stride
-Measure a distance by pacing it off and by using a meter stick
-Identify sources of error in measurement
-Evaluate estimates of measurements as reasonable or unreasonable
"What Do You See/ What Do You Think?"
Thursday, September 15th
From my perspective, it looks like they are trying to test who it takes longer
to get to the end of the measuring tape, the little kid or the young adult.
1.)Two students measure the length of the same object. One reports a length of 3 m, the other reports a length of 10 m. Has one of them made a mistake?
Most likely not, because if you look at the younger child there legs are 3 times shorter than the young adults... which 3x3 is 9 which is about 10. 2.) If the students reported measurements of 3 m and 3.01 m, do you think one of them has made a mistake?
Definitely not because the height difference in their legs are to different to have only .1 of a difference in their meters.
Investigation Lab
Thursday, September 15th
Group
Strides
Metersticks
Group
Strides
Metersticks
Jackson
David
Katie
Megan
(13strides)(.93cm)
12.09m
13.16m
Allison
Anna
Allyson
Emily
(22strides)(.5m)
11m
14cm
Samantha
Noelle
Christine
Kristoff
(20 strides)(.54m)
10.8m
13.20m
Mel
Nicky
Alex
Kim
(21strides)(.74m)
15.54m
13m
Tiffany
Krista
Jessi
Zach
(18strides)(.74m)
13.34 m
13.31
Dara
Natalie
Christine
Kaitlin
(18.3strides)(.56m)
10.25
13.5m
Avg. Stride Measurement: 12.17m
1). Do the measurements listed on your class table agree?
No the answers vary from the lowest being 10.25m and the highest being 15.54m. 2). By how many meters do the results vary?
5.29 meters separate the highest amount and the lowest amount. 3). Why are there differences in the measurements made by different groups? List as many reasons as you can think of.
People may take longer strides than others. Height is a big factor, because obviously people that are taller take larger strides than people who are shorter. 4). Suggest a method of making the class' measurements more precise. If all groups use your suggested method how will this reduce the range of measurements collected.
If everyone travels the same amount of distance the measurements will be the same, the amount of strides just may vary.
Measuring Using a Meter Stick:
1). Do the measurements listed on your class table agree?
For the most part, yes the difference in the numbers is insignificant. 2). By how many meters do the results vary?
1 meter 3). Why are there differences in the measurements made by different groups? List as many reasons as you can think of.
There may have been an error while turning the meter stick. 4). Suggest a method of making the class' measurements more precise. If all groups use your suggested method how will this reduce the range of measurements collected.
If people turn the meter stick the exact same way, the measurements should be the same. 5). What do you think would happen if each group were given a really long tape measure?
The answers would be much more accurate. 6). Can you develop a system that will produce measurements that would agree exactly or will there always be differences in measurements?
I think there will always be differences in measurements because of accidental error. Someone can always make a mistake even though they follow directions . For example, someone may use a yard stick instead of a meter stick and not know the difference. 7). Read the textbook:
a). No there were no systematic errors that were aware of.
b). When using strides, it many not have been accurate because the person taking the strides may have widened or shortened her strides every time not realizing it. When using meter sticks, we may have not accurately flipped the ruler when measuring and it could have moved an inch or two every time we flipped the ruler. Therefore not giving us an accurate measure. 9). If you did not have any systematic errors then name 3 ways a systematic error may have been introduced.
3 ways a systematic error may have been introduced by stopping a few inches from the black line while walking, using the wrong side of the ruler, and not having the ruler start at the black line when measuring the distance.
1. Systematic errors can be avoided or can be corrected by calculating. Random errors can't be corrected by calculating.
2. There will always be uncertainty in measuring because you never know when you may have an error: systematic or random. Some errors you may catch, but some errors are hard to catch because, for example, you may not line the ruler up exactly with the 1st millimeter. Not everyone has the same ruler with the same number of infinite dashes.
3. For the arrows to not be accurate or precise, the arrows would have to be randomly dispersed throughout the target. None of the arrows are close together and/or near the bullseye.
Vocabulary Words: Random Error: an error that cannot be corrected by calculation Systematic Error: an error produced by using the wrong tool or using the tool incorrectly for measurement and can be corrected by calculation. Accuracy: an indication of how close a series of measurements are to an accepted value. Precision: an indication of the frequency with which a measurement produces the same results
Do Now: "Physics Talk Review" Monday, September 19th
Photo_on_2011-09-19_at_08.17.jpg
Random errors cant be fixed
System error can be fixed.
SI System Monday, September 18th
Quantity
BaseUnit
Symbol
distance
meters
m
mass
gram
g
time
seconds
s
Prefix
Symbol
Multof100
Exp.
Kilo
K
x10^3
x1000
1km=1000m
1m=.001km
Centi
C
x10^-2
x.01
1cm=.01m
1m=100cm
Mili
M
x10^-3
x.001
1mm=.001m
1m=1000mm
Homework "Physics To Go" Monday September 19th
3.) Give an estimated value of something that you and your friend would agree on. Then, give an estimated value of something that you and your friend would not agree on.
We could agree on a ruler being one foot, but we can not agree on the length of a desk. 4.) An oil tanker is said to hold five million barrels of oil. In your estimate, how accurate is the measurement? Suppose each barrel of oil is worth $100. What is the possible uncertainty in value of the oil tanker’s oil?
Five million is just an estimate, so if each barrel is 100 dollars, that means that there is $500,000,000 worth of oil. weather that is exact or not, that is a close estimate. 6) Are the following estimates reasonable? Explain your answers:
a. A 2-L bottle of soft drink is enough to serve 12 people at a meeting: I believe that these estimates are unreasonable, i have reason to think this because if you picture a 2 liter bottle of coke and the average sized glass is 12 oz. there is not 144 oz. in that bottle. so you probably wouldnt have enough to serve 12 people.
b. A mid-sized automobile with a full tank of gas can travel from Boston to New York City without having to refuel: i dont believe this either because the average car gets 24 miles a gallon, and boston is farther away you would probably need around 1 and 1/2 gallons of gas to travel to NYC from boston. 7) If you are off by 1 m in measuring the width of a room, is that as much as an error as being off by 1 m in measuring the distance between your home and your school?
That is more of an error then measuring the distance from home to your school. the width of a room in meters is a lot less then the distance in meters from school to home. 8) You are driving on a highway that posts a 65 mi/h (105 km/h) speed limit. The speedometer is accurate within 5 mi/h (8 km/h).
a. What speed should you drive as shown on the speedometer to guarantee that you will not exceed the speed limit?
b) What could a passenger in the vehicle do while you are driving to estimate how accurate the speedometer is? (Hint: The road has mile markers, and the passenger has a wristwatch that shows seconds.)
a. you should drive a60-65 mph in order not to exceed the speed limit.
b. they could warn you for when you are going over the speed limit. 9) Its hard to keep the pedal exactly on the right speed limit, the pressure changes. if you were going 31 in a 30 there should be a little bit of leeway that they allow you.
I believe that driving 31 mph on a 30 mph road does not make a difference. That 1 mph difference is not going to cause an accident. However, I believe the limit for speeding should be 5mph. If you are 10mph over, that is a huge difference of speeding versus going the speed limit. If the rest of the cars are going 10mph slower than you, the risk of getting into an accident is greater.
Measuring a Copper Tube Tuesday, September 20th
Groups
Measurementsoftube
Gp.1
66cm
Gp.2
64.15cm
Gp.3
66.1cm
Gp.4
64cm
Gp.5
66cm
Gp.6
64.1cm
Active Physics Plus
Tuesday, September 20th
1) 10 c m {10(.01) m}
+/- .1 m--> 50.1 m - 49.9 m
+/- 1 cm -->
+/- .01 m--> 50.01m - 49.99 m
+/- .001 m--> 5.001 m - 49.99 m Random Error
2). +/- 50.01 m - 49.99 m
50m/25s = ?m/ 1s (2m/1s) 2m/1s = .02m/(t)s
t= time to swim extra distance caused by random error
2t=.02, t=.01s
Inquiring Further #1
Tuesday, September 20th
-If I was buying vegetables by the pound, gas by the gallon, or carpeting by the yard, I would expect very exact and certain measurements of each because I would actually have to pay for the amount of each I want. So if the measurement was off, I could end up paying more than I need to and that would be unfair. Also, especially with carpeting, I wouldn't want to end up having extra material because it needs to fit just right. The government, through different organizations, ensures the accuracy of commercial weighing and measuring devices at the local level. The government regulates measurement standards in quantity and quality of marketplace, and in industry measurements in mass, density, and volume.
Do Now Sec 2 p.31
Wednesday, September 21st
1. What does it mean?
The error would be systematic. Because you can correct it. 2.Why do you believe?
you can trust measurements because every measurement is proportional to the other measurements in the experiment. 3.Reflecting of section and challenge:
No it is not reasonable to say that to a cop because you should know that going 75 does not feel like you are going 30.
Investigation Activity: Wednesday, September 21st
a.) Yes that is a reasonable measurement because a football player is going to weight a lot.
b.) No that is not reasonable because no one is 13 feet tall.
c.) No that is not reasonable because 1440 minutes is 24 hours. Our teachers work no where near that a day.
d.) No that is not reasonable because poodles do not get up to 120 lbs.
e.) Yes that is reasonable, although it depends on the size of the classroom.
f.) Not reasonable. though is depends on the size of the school.
Chapter 1: Section 2
Learning Outcomes:Thursday, September 15th
-Calibrate the length of a stride
-Measure a distance by pacing it off and by using a meter stick
-Identify sources of error in measurement
-Evaluate estimates of measurements as reasonable or unreasonable
"What Do You See/ What Do You Think?"
Thursday, September 15th
From my perspective, it looks like they are trying to test who it takes longer
to get to the end of the measuring tape, the little kid or the young adult.
1.)Two students measure the length of the same object. One reports a length of 3 m, the other reports a length of 10 m. Has one of them made a mistake?
Most likely not, because if you look at the younger child there legs are 3 times shorter than the young adults... which 3x3 is 9 which is about 10.
2.) If the students reported measurements of 3 m and 3.01 m, do you think one of them has made a mistake?
Definitely not because the height difference in their legs are to different to have only .1 of a difference in their meters.
Investigation Lab
Thursday, September 15th
David
Katie
Megan
12.09m
Anna
Allyson
Emily
11m
Noelle
Christine
Kristoff
10.8m
Nicky
Alex
Kim
15.54m
Krista
Jessi
Zach
13.34 m
Natalie
Christine
Kaitlin
10.25
1). Do the measurements listed on your class table agree?
No the answers vary from the lowest being 10.25m and the highest being 15.54m.
2). By how many meters do the results vary?
5.29 meters separate the highest amount and the lowest amount.
3). Why are there differences in the measurements made by different groups? List as many reasons as you can think of.
People may take longer strides than others. Height is a big factor, because obviously people that are taller take larger strides than people who are shorter.
4). Suggest a method of making the class' measurements more precise. If all groups use your suggested method how will this reduce the range of measurements collected.
If everyone travels the same amount of distance the measurements will be the same, the amount of strides just may vary.
Measuring Using a Meter Stick:
1). Do the measurements listed on your class table agree?
For the most part, yes the difference in the numbers is insignificant.
2). By how many meters do the results vary?
1 meter
3). Why are there differences in the measurements made by different groups? List as many reasons as you can think of.
There may have been an error while turning the meter stick.
4). Suggest a method of making the class' measurements more precise. If all groups use your suggested method how will this reduce the range of measurements collected.
If people turn the meter stick the exact same way, the measurements should be the same.
5). What do you think would happen if each group were given a really long tape measure?
The answers would be much more accurate.
6). Can you develop a system that will produce measurements that would agree exactly or will there always be differences in measurements?
I think there will always be differences in measurements because of accidental error. Someone can always make a mistake even though they follow directions . For example, someone may use a yard stick instead of a meter stick and not know the difference.
7). Read the textbook:
a). No there were no systematic errors that were aware of.
b). When using strides, it many not have been accurate because the person taking the strides may have widened or shortened her strides every time not realizing it. When using meter sticks, we may have not accurately flipped the ruler when measuring and it could have moved an inch or two every time we flipped the ruler. Therefore not giving us an accurate measure.
9). If you did not have any systematic errors then name 3 ways a systematic error may have been introduced.
3 ways a systematic error may have been introduced by stopping a few inches from the black line while walking, using the wrong side of the ruler, and not having the ruler start at the black line when measuring the distance.
.75
.72
.71
.78
.76
.73
.79
.8
.84
.85
.84
.84
.82
.82
.84
.82
.81
.83
.81
.81
.81
.81
.81
.8
.82
.81
.815
.81
.814
.815
.8145
.813
.815
.814
.812
.812
.813
.812
Homework: Physics Talk
Sunday, September, 18th
1. Systematic errors can be avoided or can be corrected by calculating. Random errors can't be corrected by calculating.
2. There will always be uncertainty in measuring because you never know when you may have an error: systematic or random. Some errors you may catch, but some errors are hard to catch because, for example, you may not line the ruler up exactly with the 1st millimeter. Not everyone has the same ruler with the same number of infinite dashes.
3. For the arrows to not be accurate or precise, the arrows would have to be randomly dispersed throughout the target. None of the arrows are close together and/or near the bullseye.
Vocabulary Words:
Random Error: an error that cannot be corrected by calculation
Systematic Error: an error produced by using the wrong tool or using the tool incorrectly for measurement and can be corrected by calculation.
Accuracy: an indication of how close a series of measurements are to an accepted value.
Precision: an indication of the frequency with which a measurement produces the same results
Do Now: "Physics Talk Review"
Monday, September 19th
Random errors cant be fixed
System error can be fixed.
SI System
Monday, September 18th
x1000
1m=.001km
x.01
1m=100cm
x.001
1m=1000mm
Homework "Physics To Go"
Monday September 19th
3.) Give an estimated value of something that you and your friend would agree on. Then, give an estimated value of something that you and your friend would not agree on.
We could agree on a ruler being one foot, but we can not agree on the length of a desk.
4.) An oil tanker is said to hold five million barrels of oil. In your estimate, how accurate is the measurement? Suppose each barrel of oil is worth $100. What is the possible uncertainty in value of the oil tanker’s oil?
Five million is just an estimate, so if each barrel is 100 dollars, that means that there is $500,000,000 worth of oil. weather that is exact or not, that is a close estimate.
6) Are the following estimates reasonable? Explain your answers:
a. A 2-L bottle of soft drink is enough to serve 12 people at a meeting: I believe that these estimates are unreasonable, i have reason to think this because if you picture a 2 liter bottle of coke and the average sized glass is 12 oz. there is not 144 oz. in that bottle. so you probably wouldnt have enough to serve 12 people.
b. A mid-sized automobile with a full tank of gas can travel from Boston to New York City without having to refuel: i dont believe this either because the average car gets 24 miles a gallon, and boston is farther away you would probably need around 1 and 1/2 gallons of gas to travel to NYC from boston.
7) If you are off by 1 m in measuring the width of a room, is that as much as an error as being off by 1 m in measuring the distance between your home and your school?
That is more of an error then measuring the distance from home to your school. the width of a room in meters is a lot less then the distance in meters from school to home.
8) You are driving on a highway that posts a 65 mi/h (105 km/h) speed limit. The speedometer is accurate within 5 mi/h (8 km/h).
a. What speed should you drive as shown on the speedometer to guarantee that you will not exceed the speed limit?
b) What could a passenger in the vehicle do while you are driving to estimate how accurate the speedometer is? (Hint: The road has mile markers, and the passenger has a wristwatch that shows seconds.)
a. you should drive a60-65 mph in order not to exceed the speed limit.
b. they could warn you for when you are going over the speed limit.
9) Its hard to keep the pedal exactly on the right speed limit, the pressure changes. if you were going 31 in a 30 there should be a little bit of leeway that they allow you.
I believe that driving 31 mph on a 30 mph road does not make a difference. That 1 mph difference is not going to cause an accident. However, I believe the limit for speeding should be 5mph. If you are 10mph over, that is a huge difference of speeding versus going the speed limit. If the rest of the cars are going 10mph slower than you, the risk of getting into an accident is greater.
Measuring a Copper Tube
Tuesday, September 20th
Active Physics Plus
Tuesday, September 20th
1) 10 c m {10(.01) m}
+/- .1 m--> 50.1 m - 49.9 m
+/- 1 cm -->
+/- .01 m--> 50.01m - 49.99 m
+/- .001 m--> 5.001 m - 49.99 m
Random Error
2). +/- 50.01 m - 49.99 m
50m/25s = ?m/ 1s (2m/1s) 2m/1s = .02m/(t)s
t= time to swim extra distance caused by random error
2t=.02,
t=.01s
Inquiring Further #1
Tuesday, September 20th
-If I was buying vegetables by the pound, gas by the gallon, or carpeting by the yard, I would expect very exact and certain measurements of each because I would actually have to pay for the amount of each I want. So if the measurement was off, I could end up paying more than I need to and that would be unfair. Also, especially with carpeting, I wouldn't want to end up having extra material because it needs to fit just right. The government, through different organizations, ensures the accuracy of commercial weighing and measuring devices at the local level. The government regulates measurement standards in quantity and quality of marketplace, and in industry measurements in mass, density, and volume.
Do Now Sec 2 p.31
Wednesday, September 21st
1. What does it mean?
The error would be systematic. Because you can correct it.
2.Why do you believe?
you can trust measurements because every measurement is proportional to the other measurements in the experiment.
3.Reflecting of section and challenge:
No it is not reasonable to say that to a cop because you should know that going 75 does not feel like you are going 30.
Investigation Activity:
Wednesday, September 21st
a.) Yes that is a reasonable measurement because a football player is going to weight a lot.
b.) No that is not reasonable because no one is 13 feet tall.
c.) No that is not reasonable because 1440 minutes is 24 hours. Our teachers work no where near that a day.
d.) No that is not reasonable because poodles do not get up to 120 lbs.
e.) Yes that is reasonable, although it depends on the size of the classroom.
f.) Not reasonable. though is depends on the size of the school.