Students apply physics to real world

Students in one Elementary Physics class were recently tasked with applying some of the concepts they learned in class to the real world through an interesting activity.   

Each semester, Dr. Kent Price, associate professor of physics at Morehead State, has his students calculate the cost and energy savings of using a high-efficiency lightbulb instead of a regular incandescent bulb. Approximately 100 students per semester participate in the activity.   

“The students have to know the power (wattage) of the bulb they are replacing and the new one they are replacing it with. They must estimate how many hours per day the bulb is used. They also need to know how much they pay for electricity by the kilowatt-hour,” Price said. “Finally, they need to know how much the bulb itself cost and what the manufacturer claims its expected lifetime is.”   

By using these variables, the students can calculate the difference, which Price said teaches them about the relationship between power, energy and time as they relate to physics.   

“They learn making a relatively small change in the power rating of an electrical device or appliance can add up to significant savings in the long run,” he said.  

Price added many of his students already use high-efficiency bulbs, and so they replace a bulb at a relative or neighbor’s house. Often, Price said once they are shown the savings, many of those people switch to high-efficiency bulbs.   

“If you just go by the cost on the shelf at the store, it looks like the high-efficiency bulbs are more expensive, so many cost-conscious consumers buy the cheap bulbs on the shelf, not realizing they are paying more in the long run,” he said. “In fact, even if you ignored the electricity savings of the high-efficiency bulbs, they last five or 10 times as long as the old low-efficiency ones, so even the total purchase cost is lower for the high-efficiency bulbs.”  

Price said his students have saved thousands of dollars over the 15 years he’s used the activity in his class.  

To learn more about physics programs at MSU, visit www.moreheadstate.edu/study/physics, email maph@moreheadstate.edu or call 606-783-2930.