Monthly Archives: June 2015

Greenland Ice Sheet Trivia

Posted on 27-June-2015 by mathscinotes

I was reading an article today that says that geophysicists have figured out why the Greenland has been experiencing a flurry of magnitude 5 earthquakes. The scientists claim that the earthquakes are being caused by massive icebergs calving off the Greenland ice sheet in a manner that momentarily jams the movement of the ice sheet. The ice sheet and the calved iceberg are so massive that their interaction cause an earthquake.

While the earthquake information was interesting, there was a side discussion on the amount of ice required to raise sea level by 1 mm and seal level impact potential of a melting Greenland ice sheet. Continue reading →

Posted in Geology | Comments Off on Greenland Ice Sheet Trivia

Owl Camouflage

Posted on 26-June-2015 by mathscinotes

I saw these two pictures today and I was stunned by the effectiveness of an owl's camouflage. I occasionally see owls – there is a great horned owl that lives near my house and it is amazing watching it fly at dusk. It has a very large wingspan. Continue reading →

Posted in General Science | Comments Off on Owl Camouflage

Lignum Vitae is a Remarkable Wood

Posted on 24-June-2015 by mathscinotes

I enjoy woodworking very much and I am now in the process of making a solid walnut countertop by gluing small walnut pieces together. While choosing the wood species for my countertop, I did consider a number of tropical species like teak and ipe. During this search, I heard a person mention that Lignum Vitae was the world's densest wood and is known for being so oily as to be considered self-lubricating. It is also a rare and potentially endangered species. Continue reading →

Posted in Construction | 1 Comment

Barycenter of Pluto and Charon

Posted on 18-June-2015 by mathscinotes

I am excited about the New Horizon's flyby of the Pluto system (Figure 1) occurring on July 14, and I will be glued to my computer as the data is returning. Fortunately, there is already some data coming back on Pluto and its moons. One interesting aspect of the Pluto system is the fact that the mass ratio of Charon to Pluto is large enough that the barycenter of their orbit is outside the bodies of both Charon and Pluto. Continue reading →

Posted in Astronomy | 9 Comments

Volt-Ampere Measurement Circuit

Posted on 8-June-2015 by mathscinotes

This is a circuit designed by Stephen Woodward that I saw years ago in EDN. I originally was interested in the right-hand side of the circuit, which measures the real power usage of the load. I now have an interest in the left-hand side of the circuit, which measures the Volt-Ampere (VA) usage of the load. I will present an abbreviated analysis of the circuit Continue reading →

Posted in Electronics | Comments Off on Volt-Ampere Measurement Circuit

Sun's Galactic Orbital Speed

Posted on 4-June-2015 by mathscinotes

I was reading Quora this week and I saw the following statement that mentioned the orbital speed of the Sun as it revolves about center of the Milky Way. Continue reading →

Posted in Astronomy | Comments Off on Sun's Galactic Orbital Speed

Schmitt Trigger Circuit For a Push-Pull Output

Posted on 3-June-2015 by mathscinotes

I previously wrote a blog post about how to select components for a Schmitt trigger circuit using a comparator with an open-collector output. An engineer stopped by my cube yesterday and asked if I could write-up the same analysis for a Schmitt trigger circuit using a comparator with a push-pull output. This post will provide that analysis. The only thing unusual about the circuit is the use of a Zener diode as a voltage reference instead of the more commonly seen resistor divider network. Continue reading →

Posted in Electronics | 2 Comments

Number of Photons Per Second from a One-Watt Bulb

Posted on 2-June-2015 by mathscinotes

An article on Stumbleupon and called "8 shocking things we learned from Stephen Hawking's book" considered the following statement from The Grand Design shocking.

A 1-watt night-light emits a billion billion photons each second. Continue reading →

Posted in General Science | Comments Off on Number of Photons Per Second from a One-Watt Bulb

Compensating GPS Clocks for the Effects of Relativity

Posted on 1-June-2015 by mathscinotes

I occasionally read articles on Stumbleupon and I came across an interesting article called "8 shocking things we learned from Stephen Hawking's book" – the book they are referring to is called "The Grand Design". I personally would not call the statements in the article shocking, but that is just my opinion. Continue reading →

Posted in Navigation | 5 Comments