Some Physics Questions

Looking at the title of this blog, many of you must be wondering when the the physics will appear.  I still do spend time on physics, but mostly wrestling with fundamental issues. For example: if, as Einstein  indicates in his "Meaning of Relativity" and other writings, that spacetime is really the interval  between events, what are the implications of this with regard to the propagation of fields? Does energy/matter curve spacetime, or actually create it it? Is this why spacetime is "denser" near masses?

Why the different signs for space and time; energy and momentum? What is the reason for the the imaginary component of spacetime?  How does it relate to velocity vs displacement for rotating bodies?

Of Ice and Men

While clearing some of the walk way I noticed the following:

Moving a large block of ice is nearly impossible. The surrounding pieces  reinforce it and give it the strength to resist large forces. However, if you chip away at a piece and separate it from the supporting pieces around it, you can clear it away pretty easily.   It's pretty much the same with an individual person and groups of people, especially mobs.

Coping with Winter

Inspired by my good friend Tom, I took to raking snow off my roof yesterday. Not being as tough as Tom I 1) wore socks (and boots) 2) wore long sleeves and a jacket and 3) had to climb up on the porch roof. I cleared an area about 12x25. The snow is about 2 feet deep rising to about 3 feet at the ridge.

After raking down this pretty dense stuff and having to leave about half of it, I was glad I reinforced the rafters under this roof three years ago.

Thoughts from a winter forest

I was snowshoeing the other day and there were strong gusts. I spent a lot of time listening to wind in the trees. The poet in me thought he heard the trees breaking their shackles of ice, bending to the will of the wind. The physicist in me thought the bigger trees were experiencing about ten thousand foot pounds of torque. The scout leader in me thought how embarrassing it would be if I had to be rescued from under a fallen tree.

Project Report: Second Night Stand completed

I think I got it close to right this time. Nature made the nicely figured wood for the drawer front and an English foundry cast the draw pulls, but I'll take credit for the legs.

The two night stands took about 2 months, with lot's of travel, shoveling, and snowshoeing interfering. My hand dovetailing has gotten pretty good. Proves that with enough practice even the untalented may succeed.

A visit to College of the Holy Cross

Went to Worcester ( the recently crowned snowiest city in the US) Friday to visit Sarah V at the College of the Holy Cross. Holy Cross is on a steep hill overlooking Worcester. It has some lovely buildings including a beautiful library and main building with a very impressive, traditional looking hallway. And of course it has Sarah.

Winter Report

Up to a balmy 2 degrees now with gusts only about 30 mph.  Last Thursday morning it was -6 F during a brief morning walk with 25 mph winds. There are many nice things about -6: the ice is too cold to be slippery, there are no mosquitoes,..... and I forget the rest.

Earlier in the week I looked at the results of my shoveling and concluded they were near nil ( except the porch roofs are still standing):

Before

After

After After

But it is lovely, ......

a local driveway:

Music review

 Went to a concert by the Pioneer Valley Symphony last night. The soloist was a 14 year old violinist, Ilana Zaks. She played the Mozart Concerto No. 3 as well as I have ever heard it played, including recording of the masters; and the same for her playing Sarasate's Zigeunerweisen, gypsy music. If you ever have the opportunity to hear her, take advantage of it.

The concert also included a wonderful overture to Armida, by Haydn, and Beethoven's Second Symphony. I was once again reminded that classical music is one of mankind's greatest achievements and that Beethoven transcends even the greatness of classical music.

Please attend concerts when you can. It will add beauty to your life and you will be helping to preserve a great pillar of civilization.

Training for The Winter Olympics

Yesterday I started training for what is sure to be the next big Winter Olympics Event: porch roof shoveling. While it's a little less entertaining than snowshoeing it certainly provides opportunities for exercise. I figure between the 18" of snow and the 3 inches of ice I must have moved about a ton of stuff.

Here are the before and afters:

Maybe we should read those things

It's amazing what reading instructions can do. We had noticed that Natalie, the upstairs cat in this house, was reluctant to use her drinking fountain (doesn't every cat have their own drinking fountain?) so I decided to order new filters. Looking through the instruction book for the item number, I saw a) that the pump could be disassembled for cleaning , b) and this should be done every couple of weeks. Realizing that a year was more than a couple of weeks( I am quick that way) I disassembled the pump and found enough growths to provide at least one Ph.D thesis in bacteriology, and perhaps a middling length career.

Winter is truly here

It hit -6 this morning but is now a toasty 10 F. It certainly is the white season here: 14'' on Monday and another 5 or 6 last night and this morning; and cold enough for it to all stick around. Here are some photos from some recent snow falls  

the backyard with the snow shoe track, 

some pictures of the forest just north of our house, 

and a shot of the best mode of transportation for breaking trail on 20" of new snow.

More Physics

Today being a snow day ( kind of irrelevant when you are retired), and since I had to wait for some too thick shellac to dry on my nightstand, I had time for more of the physics problems that Mr. Gilmore of Ridge sent me. I have to admit that, contrary to my normal philosophy of in rotational motion viz. angular velocity omega is everything - nearly, I used the velocity to find perigees for orbits, given the  radius and velocity at the apogee. However, you can only use  the total velocity x radius  at the apogees and perigee to calculate the conserved quantity, angular momentum, because the velocity has non tangential ( i.e some radial ) components elsewhere in the orbits. Thus, if you need  to know the velocity at other points you can find the total speed using conservation of energy given the radius, but to find the direction you would find the  tangential or angular velocity using conservation of angular momentum and  omega r^2 is the conserved quantity.

I am now waiting for Mr. Gilmore to let me know if my latest efforts yielded correct answers.

Snow Report and a nightstand nears completion

We dodged the big one last week, getting only 5 inches compared to 30" elsewhere, but we are getting our fair share today. About  14" and near zero temperatures equal a real dose of winter. Hope to get out and snowshoe some tomorrow... after some shoveling.

In the mean time, I am creeping up on completing one of two mahogany nightstands.  Here are a couple of pictures; sideviews. "Just" need to rub out the last coat of finish and make the drawer ( nine pieces including four hand cut dovetail joints- thus the quotation marks around the just.)