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Next week, Prof. Shaul Hanany will lie on a bed of nails while someone takes a hammer and smashes a cement block on his stomach. But he’s not worried. Really. He knows that physics is on his side.

Hanany is a member of the University of Minnesota’s Physics Force, a troupe of professors and science teachers who use flashy stunts and slapstick humor to convey the joy of physics to (mostly young) audiences.

The Force, which has performed its trademark “Physics Circus” for nearly 30 years, is returning to Northrop auditorium next week with a series of daytime shows for school kids and an evening show for the public on Jan. 14. (Tickets are free with reservations.)

Like all the demonstrations in the hourlong show, the nail-bed trick is designed to make a point, said Hanany. It shows the power of physics to amuse and fascinate people. “There’s this notion that physics is complicated and difficult and always goes above your head,” he says. “It’s not. That’s exactly what we want to show. Physics is fun.”

Hank Ryan, a retired Mounds View science teacher, has been performing with the troupe since he helped found it in 1985. For many years, he was the guy on the nail bed. “It’s very dramatic,” he laughs. Physics literally cushions the blow. “Each nail supports some of your weight, and collectively they all support you, and none of the nails actually hurts, too much.” Inertia, meanwhile, keeps the cement block from causing harm when it’s hit from above. “It doesn’t move much, even though it gets smashed.” Of course, the performers warn the audience not to try this at home.

Other crowd-pleasers: Watching a 55-gallon drum crushed by a change in air pressure. And the “monkey drop,” when a performer is dropped from a 20-foot crane as a ball is shot at him from a cannon. Once again, physics saves the day. “It illustrates that gravity acts the same way on the ball” as the person, said Ryan. “They fall at the same rate.” So the performer catches the ball. “Most times.”

For reservations, go to www.eventbrite.com and look up Physics Force.

maura.lerner@startribune.com