Past Articles:

This month’s topic: TECHNOLOGY

Do roller coasters have brakes?

Yes, roller coasters have brakes. A roller coaster uses a brake system in order to stop exactly at the end of the ride and also in case of emergencies. Unlike trains, brakes are not built into the roller coaster itself; instead, the brakes are built into the tracks. A series of clamps are placed at the end of the track as well as various select points along the tracks. A computer operates the braking system that closes these clamps when the roller coaster needs to stop.

How does a GPS work?

Over every place in the world and at all times, there are at least four GPS satellites that are “visible” by a GPS receiver. At regular intervals, each satellite transmits information about its position and the current time. These signals, traveling at the speed of light, are intercepted by your GPS receiver, which calculates how far away each satellite is, based on how long it took for the messages to arrive. A GPS receiver's job is to locate four or more of these satellites, figure out the distanc­e to each, and use this information to pinpoint your exact location.

How does the E-Z Pass work? 

The E-Z Pass is a wonderful example of RFID technology. RFID (Radio Frequency Identification) is the generic term for technologies that use radio waves to automatically identify people or objects. This system makes use of a tag, which is made up of a microchip with an antenna, and a reader, which also has an antenna. An example of a RFID tag is the E-Z Pass tag in a car. The E-Z Pass reader that you drive up to in the E-Z Pass lane sends out radio signals that seek out any E-Z Pass tags within range. The E-Z Pass tag in your car then responds by sending out the code with the information needed by the reader.

Question of the Month:

This month’s question was submitted by Moshe of Brooklyn, NY.

Dear Professor, What does NASA stand for?

Dear Moshe, The space program in the United States is called NASA, which stands for National Aeronautics and Space Administration. Aeronautics is the science of flight. This term comes from Greek words that mean “air” and “navigation.”