麻豆传媒

Late in 2019, in a small classroom on the fourth floor of Smith Hall, Towson University students got up close and personal with a basic tenet of physics: the speed of light. 

鈥淭he students in PHYS 242 have spent the semester learning about electric and magnetic fields. Now, they have just learned that these two fields are actually two sides of the same coin鈥攁nd that the 鈥榗oin鈥� is light itself,鈥� says James Overduin, an associate professor in the Department of Physics, Astronomy and Geosciences. 

During the demonstration, the students split a laser beam into two. One reflected off a mirror to a detector after a short distance. The other passed through the mirror and continued further before reflecting off another mirror toward a second detector. Using the times recorded, the students were able to calculate light鈥檚 speed: 670,616,629 miles per hour. 

The experiment itself took considerably longer to develop. Research students Jon Perry, Carmen Cuestas and Calin Reamy began in the summer to finetune the procedures and techniques needed to achieve an accurate measurement.

鈥淛on showed up at all hours to test and improve the apparatus and was never satisfied, always thinking about how we could be more certain of the measurement and its accuracy. Without him, it would not have happened,鈥� stresses Overduin.

The students originally directed the laser 120 meters down the length of Smith Hall鈥檚 main hallway. When they continued to be interrupted by foot traffic, the group came in at night to record measurements. 

Overduin also credits staff members Jeff Klupt and Jim Selway for their parts in the experiment. Klupt, the department鈥檚 electronics shop manager, 鈥渞escued鈥� the demonstration, according to Overduin, by building a modulator to replace a malfunctioning measuring component. Overduin describes teacher-in-residence Selway鈥檚 energy and enthusiasm as 鈥渃rucial鈥� to the success of the experiment.

Now was the perfect time for students in PHYS 242 to see the demonstration since the next class in the introductory physics sequence acquaints students with the concepts of waves and relativity.

鈥淚 really want students to understand physics,鈥� says Overduin. 鈥淣ot only in a theoretical way but because they have seen it for themselves. Then all the rest of relativity theory follows, including the conclusion that the past, present and future are all equally real. They don't 鈥榟appen,鈥� they just 鈥榓re.鈥� That's the kind of incredible leap that caused me to fall in love with physics and what I hope to share with my students through demonstrations like this.鈥�

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Studying physics at TU

The physics major offers flexible options to prepare you for graduate study in fields such as physics, astrophysics, medicine and engineering. Undergraduate physics majors can choose from the following concentrations: general physics, applied physics, astrophysics and physics secondary education. Individualized programs emphasize optics, elementary particle physics, solid state physics, nanotechnology, electronics and nuclear physics.

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