Making Heat Pumps Better with a Common Ingredient
Heat pumps are a great way to use the power (and heat) of thermodynamics to move heat from a cold space to a hot space. Their Coefficient of Performance (COP) makes them a better option than fossil fuels in some climates. Renewable energy like solar, can also reduce the carbon footprint. However, the biggest problem […]
Welding Symbols
Watch our video! One of the most important standards in machine design are those specified by the American Welding Society. In one symbol critical information about the required weld is provided, such as location of the weld, type of weld, and size of the weld. If there are two sides to the connection, the symbol […]
MECHANICAL PE EXAM TIP – Units, Units Units!!!
If I wasn’t Dr. Tom, I’d be Dr. Units. I cannot tell you how many times units are the reason someone gets the wrong answer to a problem. It might be as simple as inches needed to be converted to feet, or the other way around. Or, it is a combination of units like gallons per minute […]
Turn Complex Motion into Clear and Understandable Solutions
Watch our video! One of the most common and useful mechanisms in machine dynamics is the “slider-crank.” It has three elements: the “slider”, the “crank”, and the “connecting rod.” The slider is in “pure translation”, moving back and forth in a straight path. The crank is in “pure rotation”, moving in perfect circular motion. Then, […]
The Dr. Tom Method – The Perfect System to Pass the PE Exam
At Dr. Tom’s Classroom, we’ve worked hard to create the perfect system to help Mechanical engineers pass the PE Exam and become Professional Engineers. With PE Exam Review courses for all three Mechanical PE Exams (HVAC & Refrigeration, Machine Design & Materials, and Thermal & Fluid Systems), we can help you pass the PE Exam. […]
Simplify Distributed Load Analysis With This Proven Method
Watch our video! Distributed loads appear in a great variety of problems, the most common being loadings on beams. This video shows how to replace the three most common distributed loads with a single force at a single location. These loadings include rectangular, triangular, and trapezoidal. Note that a trapezoidal loading can be treated as […]
The Automotive Differential – lots and lots of gears!
While being absorbed watching videos on a popular social media site, a video appeared talking about the need for a differential on your car. It was very short and didn’t provide a satisfactory explanation of how the design evolved. I searched the internet and discovered a very unique discussion of the principles involved. Surprisingly, it […]
PI – Around and around we go!
Today is PI Day and if there is any number that should be celebrated it is PI. PI shows up in so many formulas and equations in math and science and engineering that it would be virtually impossible to make even a passable list. For mechanical engineers, anything rotating “around and around”, like gears, will […]
FEATURED TESTIMONIAL – “I Trusted the DTC Method and I Passed!”
“Just got the results back for the ME: TFS Exam, and I passed. I believe the DTC method of taking the exam is the ultimate make or break in passing this exam. After going through Doctor Tom’s Classroom, I felt confident with all of the material with the exception of maybe cycles. As I went […]
Microalgae to Fuel a Tropical Paradise
Researchers at the University of Hawai’i are working on engineering microalgae – small photosynthetic organisms, to produce useful organic compounds like lipids and other long chained molecules. These can be easily converted into fuels and medicine. The key is rewriting the DNA so that the desired compounds are made in large quantities without hurting the […]
