Warm Up 99/12/11
-
Upload
karleigh-wilkinson -
Category
Documents
-
view
15 -
download
2
description
Transcript of Warm Up 99/12/11
![Page 1: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/1.jpg)
Warm Up 9Warm Up 9 9/12/11 9/12/11
How many significant figures are in 80900?
Warms up will be checked Wed.
![Page 2: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/2.jpg)
TestTest
Curve was 5 points
![Page 3: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/3.jpg)
Guaranteeing Partial Credit
1. Organize what the problem gives you
2. Make a drawing if necessary3. Identify the equation you will use4. Fill in the equation with the
givens5. Show your work6. Circle your answer with the
proper units
![Page 4: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/4.jpg)
GradesGrades
Still behind in grading menus
![Page 5: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/5.jpg)
Significant Figures and UnitsSignificant Figures and Units
Are required for correct answers from now on
Correct me
![Page 6: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/6.jpg)
4 Rules to Significant Figures4 Rules to Significant Figures
![Page 7: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/7.jpg)
Rule 1Rule 1
All non-zero digits are significant.
◦5 m◦76 m/s◦4567 m/s2
◦94586 N
![Page 8: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/8.jpg)
Rule 2Rule 2
All zeroes between significant digits are also significant.
◦30,505 kg◦50,500 s◦50,000,005 m/s◦02020 m
![Page 9: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/9.jpg)
Rule 3Rule 3
Zeroes to the right of a decimal or another significant digit are significant.
◦2.00 N◦570.090 J◦56.000 A◦500.
![Page 10: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/10.jpg)
Rule 4Rule 4
Zeroes used to for spacing are NOT significant.
◦0.2 W◦0.002 V◦0.00200 km◦1.00200 km
![Page 11: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/11.jpg)
When to useWhen to use
In problems, the least sig fig rules them all.
A car can accelerate from zero to 12 m/s in 4.65 seconds. What is its average acceleration?
![Page 12: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/12.jpg)
When to useWhen to use
ONLY apply significant rules to the final answer◦Calculators are good at being accurate
A car can accelerate from zero to 12 m/s in 4.65 seconds. What is its average acceleration?
![Page 13: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/13.jpg)
Kinematic ConceptsMotionRequires a change in distance/displacement
Change in distance/displacement must occur over a period of time (rate)
![Page 14: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/14.jpg)
Difference Between Scalars and VectorsIn the end, does this sailboat
have a displacement?
![Page 15: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/15.jpg)
Kinematic ConceptsAverage SpeedBasic motion = ∆d / ∆tSpeed is the rate of change of
distance◦Speed = change in distance
over time◦Formula:
savg = ∆distance / ∆time
![Page 16: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/16.jpg)
Kinematic ConceptsAverage VelocityBasic motion = ∆d / ∆tVelocity is rate of change of
displacement◦Velocity = change in
displacement over time◦Formula:
vavg = ∆displacement / ∆time
![Page 17: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/17.jpg)
Difference Between Scalars and VectorsA car is going due north at 60
km/hr.Another car is going due
south at 60 km/hr.Do the cars have the same
speed?Do the cars have the same
velocity?
![Page 18: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/18.jpg)
Kinematic ProblemsSpeed and VelocityAn ostrich can run at speeds
of up to 72 km/h. How long will it take an ostrich to run 1.5 km at this top speed?
![Page 19: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/19.jpg)
Perfect Physics World
One model of physicsNo friction or air resistance
![Page 20: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/20.jpg)
Kinematic ConceptsAverage VelocityMotion = ∆d / ∆tSpeed is the rate of change of
distanceVelocity is rate of change of
displacementVelocity and speed tell you how
fast position is changing, not just a change in position.
Average velocity = ∆d / ∆t
![Page 21: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/21.jpg)
Kinematic Vocabulary
Average Velocity◦Can velocity be higher or lower
than average over the same period of time?
Instantaneous Velocity◦An object’s velocity at a specific
moment in timeConstant Velocity
![Page 22: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/22.jpg)
Warm Up 10 9/13/11
Estimate the velocity the chair you are sitting on.
Hint: There are at least 3 velocities.
![Page 23: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/23.jpg)
Frame of Reference
“Frame of Reference” is similar to “point of view”
Motion is relative to the Frame of Reference
![Page 24: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/24.jpg)
0 m/s
4 m/s
2 m/s
5 m/s
![Page 25: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/25.jpg)
Your Frame of Reference is considered 0
Objects going in opposite directions – Add
Objects going in the same direction - Subtract
![Page 26: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/26.jpg)
Practice Problem
What is the relative speed of 2 cars heading towards each other if one car is traveling 12 m/s and the other is 33 m/s?
What is the relative speed if the fast car was trying to pass to slow car?
![Page 27: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/27.jpg)
Kinematic Vocabulary
Displacement is change in position
Velocity is change in displacement over time
Acceleration?
![Page 28: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/28.jpg)
Kinematic ConceptsAccelerationAcceleration is the rate of
change in the magnitude AND/OR direction of velocity.
Acceleration occurs when:◦Speed (magnitude) increases or
decreases◦Velocity changes direction
![Page 29: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/29.jpg)
Average Acceleration
2if
avg
aa
t
va
![Page 30: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/30.jpg)
Is there acceleration?From a dead stop, a car hits the
gas and goes 100 m in 3 s.A car moves at a constant
velocity of 10 m/s. Ahead, a cat starts to cross the street. The car hits the brakes!
A car is driving around in a perfect circle at a constant speed.
![Page 31: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/31.jpg)
Water drips from the ceiling at one drop per second. As the drops fall, what is their relative distance?
Is the distance between 2 drops the same, increases or decreases?
![Page 32: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/32.jpg)
2if
avg
aa
t
va
t
dvavg
![Page 33: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/33.jpg)
How acceleration changes motion.
Accel.VelocityDisplace-ment
t=0
t=1s
t=2s
t=3s
t=4 s
![Page 34: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/34.jpg)
Practice Problem
A car drives for 1 hour at 20 km/h. Then it drives for 1 hour at 30 km/h. What is the average speed of the car?
Did the car undergo any acceleration?
![Page 35: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/35.jpg)
Kinematic ProblemsSpeed and VelocityIf Hawaii is 2.24 x 103 km long
and the moves at an average speed of 50. mm per year, how many years would it take to move the length of Hawaii?
![Page 36: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/36.jpg)
Kinematic ProblemsSpeed and VelocityJupiter, the largest planet in
our solar system, has a radius of about 7.1 x 104 km. Its period of rotation, however, is only 9 h, 50 min. Calculate the average speed (in km/hr) for one rotation. What is the average velocity?
![Page 37: Warm Up 99/12/11](https://reader036.fdocuments.in/reader036/viewer/2022062422/56813815550346895d9fca5b/html5/thumbnails/37.jpg)