Tuesday, February 12, 2019

Blizzard Bag #1 - Factor Label Unit Conversion

Winter 2018-2019 
Factor Label Unit Conversion

Numbers alone, numbers without units, "naked numbers"  are seldom used.
One of your blizzard bag questions is to find examples when it is okay to use a number without a unit.

The factor label unit conversion method is a way to convert an amount with one unit into an equivalent amount with a different unit.  For example it shows how to convert from 200 cents to $2

If you do not have internet access, do the practice worksheet handed out in class and answer the questions below.

If you have internet access, go to the following website and do all the problems.  Make paper copies of each problem you do.  Also answer the questions below.

website:   Factor Label Practice Problems

  Read the article below "Naked Numbers Cost NASA" to understand why putting units with your numbers is important.  

Questions for all to do:

1.  Find times when it is okay to use a number without a unit.

2.  Comment on how the following story can be possible:

I was driving north from Vermont to Quebec.  After I entered Canada the speed limit changed from 65 to 100  so I slowed down a little.

3.  Give an example when   1 = 1000

4.  Find the unit that currently has the record for being the largest.

5. Why use units with your number?

Bring responses on paper to class tomorrow

Naked Numbers Cost NASA
Mars Climate Orbiter Gone Forever

After a nine month trip to Mars, the Mars Climate Observer spacecraft
was lost as a result of Naked Numbers.  Numbers communicated from
Lockheed Martin in Colorado to NASA's Jet Propulsion Lab in California
were left unit-less.  Naked numbers, being completely meaningless,
left engineers to guess at their meaning.  The confusion created by
improperly dressed numbers caused the loss of a $125 million
spacecraft and the waste of a 9 month journey to Mars.  Thankfully, no
lives were lost.

Lockheed Martin was sending daily course adjustments to the Jet
Propulsion Laboratory with numbers that should have been wearing the
English units of "pound-seconds" to describe the amount of impulse
which should be applied to the spacecraft to adjust its course.  When
these naked numbers arrived at the Jet Propulsion Laboratory engineers
assumed that these were specifying the amount of impulse in metric
units of "newton-seconds".  Simply labeling the units that were being
used would have prevented this tremendous loss.  A group of physics
teachers in Ithaca, New York hope to bring a proposal to Capitol Hill
that would ban the use of naked numbers in the United States.  Further
efforts are being used to convince the United Nations to apply a
similar law to the World.  Until such a law is passed, physics
teachers everywhere will have to settle for simply marking answers as
wrong if they are not labeled with proper units.  Math teachers are
urged to contribute to the solution not the problem.

Mars Orbiter Loss Linked to Math Mistake

Newsday - Ithaca Journal
October 1, 1999

Washington - The loss of the Mars Climate Orbiter as it approached
Mars last week is being blamed on a goof that could have tripped up a
novice science student - confusing English and metric units.
    A preliminary investigation has found that two spacecraft teams -
one at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the
other at a Lockheed Martin facility in Colorado where the spacecraft
was built - unknowingly were exchanging some vital information in
different units of measurement.
    Thomas Gavin, deputy director of space and earth sciences at JPL,
said in an interview Thursday that the mistake involved information
being used to make tiny corrections in the spacecraft's orientation
during its 9½-month cruise to Mars.
    Twice a day during the cruise to Mars, tiny thrusters on the
spacecraft were fired briefly to counteract the effects of solar wind
and other forces on the spinning of the flywheels.  The spacecraft
team in Colorado used English units called pound-seconds to describe
the small forces.(bad scienc writing)
    That data was shipped via computer to JPL where the navigation
team was expecting to receive the information in newton-seconds, a
metric measure of force. (bad science writing)
    Two Cornell University scientists calibrated the camera on the
spacecraft, but neither scientist had any involvement in the
measurement mistake.

Monday, February 11, 2019

Astronomy Blizzard Bag #3 - How do elements heavier than iron form?

Astronomy Blizzard Bag #3 - How do elements heavier than iron form?

Blizzard Bag Instructions:

Go to the following website:


1.  Watch the Video about how gold forms

2.  Click on "Think" and write out on paper the questions and your best answer to the questions.

3.  Click on "Dig Deeper" and read further on the topic

4.  Click on "Discuss" and read through the discussions

5.  Answer the following:  Distinguish between the s-process and the r-process.  Write a paragraph explaining each and the conditions necessary for each.

Thursday, January 17, 2019

Physics Blizzard Bag #3 - Static Electricity

Physics Blizzard Bag #3 -  Static Electricity

Blizzard Bag Instructions:

1.  Go to the following website:


2.  Watch the video.

3.  Click on "Think".   Write out on paper each question and your best answer to each question.

4.  Click on "Dig Deeper" and read about the topic.

5.  Click on "Discuss" and read through the discussions on static electricity.

6.  Write down at least 2 examples of your personal experience with static electricity.

Saturday, November 17, 2018

Blizzard Bag #2 Using the Scientific Process to Design and Perform an Experiment

Mr. Merrell's Blizzard Bag #2
Winter of 2019

Purpose: To experiment with virtual  projectiles, form a hypothesis and design your own experiment
Introduction:  On the University of Colorado website you will gain  access to the following items: a tank shell, a golf ball, a baseball, a bowling ball, a football, a pumpkin, an adult human, a piano and a Buick. You will be able to LAUNCH them. This could be fun! It's your turn to design an original laboratory activity to test a specific hypothesis.  See what things you can change (independent variable).  See what changes when you change your independent variable (your dependent variable).  Pick just one IV and one DV.  Keep track of the numbers.  Graph the DV on the vertical axis and the IV on the horizontal axis.  Look for a relationship.

Materials: Projectiles simulation, University of Colorado or create your own launcher using a rubber band, something to shoot, and a measuring tape


  1. Go to the Projectiles simulation, University of Colorado and try out some launches. If this does not work, create your own physical laucher.
  2.  Select a purpose for your lab or formulate your own testable hypothesis.
  3. Design your experiment based on the purpose or hypothesis you have formulated. It is important that you limit your experiment to only two variables that can be easily measured and compared, all other variables should be kept constant.  For example, you can choose to vary the angle and measure the range (horizontal distance traveled).
  4. Be sure to include the following sections in your design: Title, Purpose or Hypothesis, Introduction, Materials, Procedure, Data Table, Graph, Questions, and Conclusion.

Wednesday, May 30, 2018

Teach Your Own Chapter Astronomy Project

Chapter 6 Solar System

Solar System Slide Show

Solar System Slide Show

Chapter 7  Earth

Chapter 7 Slide Show - B

Chapter 8   Moon and Mercury

Moon and Mercury Slide Show

Second Slide Show - D

Chapter 9 Venus

Venus Slide Show

Second Slide Show - D

Chapter 10 Mars

Chapter 10 Slide Show - B

Chapter 11   Jupiter

Jupiter Slide Show

Chapter 12   Saturn

Saturn Slide Show

Saturn Slide Show

Chapter 14 Solar System Debris

Chapter 14 Slide Show - B

Chapter 14 Slide Show

Chapter 16  The Sun

Chapter 16 Slide Show - B

Chapter 17  Red Giants and White Dwarfs

Chapter 17 Slide Show - D

Chapter 17 Slide Show

Chapter 19  Star Formation

Chapter 19 Slide Show - B

Chapter 20  Stellar Evolution

Chapter 20 Slide Show - B

Chapter 21  Stellar Explosions

Chapter 21 Slide Show

Chapter 22  Neutron Stars and Black Holes

Chapter 22 Slide Show

Chapter 23  Galaxies and Cosmology

Ch 23 Slide Show - D

Chapter 23 Slide Show

Chapter 25  Galaxies and Dark Matter

Ch 25 slide show - B

Chapter 25 Slide Show

Chapter 26  Cosmology

Chapter 26 Slide Show - B

Chapter 27  The Early Universe

Chapter 27 Slide Show - B

Tuesday, January 17, 2017

This is the QR code to get you to the Physics 2019 PowerPoint presentations

Here is the link to the website that has the chapter slide shows!

The Physics Slide Show Website