Day 19: Put On Your Physics Goggles

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College-Prep Physics: I didn’t anticipate spending a whole period about how a fan cart works. Nor was I expecting students to say a fan cart’s speed would accelerate up to a constant speed.

Transfer is hard. We had already done the bowling ball and mallet activity. But this wasn’t a bowling ball. It was a fan cart. In their minds, different objects means different outcomes.

That’s when I came up with the idea of “physics goggles.” When you’re wearing your physics goggles, you see past the superficial features of different situations and focus on the underlying principles. In the case of the fan cart, the air molecules were providing the “taps” to accelerate the cart. And since those “taps” never stop, the cart would continually increase speed, just like a tapped bowling ball.

While students agreed that you could get the bowling ball to go as fast as a Ferrari (even with tiny taps, as long as you could keep up with the ball), they initially struggled with the fan cart going as fast as a Ferrari. Most thought the top speed of the fan cart was determined by the speed of the fan.

“Time to put on our physics goggles!”

##BFPM

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About Frank Noschese

HS Physics Teacher constantly questioning my teaching.

2 responses to “Day 19: Put On Your Physics Goggles”

  1. John Burk says :

    This is a great idea. I’ve preciously talked about free body diagram glasses that let you see the forces acting on an object, but physics goggles is an even more powerful extension of this idea.

  2. mrstokes24 says :

    Love the idea of physics goggles. I would like to add safety sides to them representing preconception blinders!

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