First, upon awakening, do you recall your dreams? Dreams early in the night usually incorporate experiences of the final waking hour, such as conversations or late-night TV. Later dreams are far more surreal. Not remembering any of them is a sign of a deep sleep - a good thing.
Eyes now open? Glance at the window. If air conditioning has been on, "steam" on the far side of the glass means the dew point is higher than room temperature: proof of extreme humidity. Moisture on the outside of windows is common in southeastern states, but fairly rare here. Bad news; dress for a sticky day.
Does the curtain pull itself inward toward your leg when you turn on the shower? Powerful jets of water from the showerhead produce this effect: It's Bernoulli's Principle. Whenever liquid or gas moves quickly, pressure is reduced. It's a bit counterintuitive. The fast water-stream pulls along some adjacent air with it, creating a partial vacuum that sucks in the curtain. This same principle makes tornadoes lift roofs and lets airplanes fly.
Now you're in the car. At a stoplight, notice how metals around you (like motorcycle chrome and the bumpers of trucks) gleam. Interesting process: Metals have outer electrons capable of absorbing and then reemitting photons of light, while their inner electrons are locked in place with too little flexibility to vibrate and emit light. Result: Sunlight hitting metals is not absorbed, nor does the light pass through. Instead, the light's reflected only from their outer electrons, making metals neither transparent nor dull, but something else: gleamy.
Next stop, look up to see if you can spot the moon. One week each month you'll easily see it in the morning sky, in the south or west. It will never be full and will always be lit up on the left side. This is the waning moon, usually a half-moon or nearly so: the phase that lies in front of us as we orbit the sun. Look its way and you're facing forward as our planet hurtles through space. Cool stuff. When the morning moon's ahead of you, you're going 66,000 miles per hour over the speed limit. You'll be right there, where the moon is now, in 3 1/2 hours.
As you drive, your car gets warmer. Humans each radiate about the same heat as a 100-watt bulb. You and a few passengers will warm it up quickly. Daylight, entering windows but being unable to exit as infrared, heats it even more. Praise be to auto A/C, first introduced in the 1940 Packard. (The machinery took up the whole trunk).
On a sunny summer day you might see a mirage on the road: a pool of water that's not there. Very hot air just above the asphalt is so thin that light increases its speed compared with the cooler, denser air a few inches higher up. When light changes speed it bends - a process called refraction. Refraction makes a spoon in a half-glass of water appear bent, too. It makes that glass cola bottle seem to hold twice as much as it really does. No accident.
On the highway, you roll down your window. Whoops! Your important loose papers get sucked out. But now you know why: Bernoulli's Principle again. Your car's motion produces a stream of rapidly moving air outside. Fast air motion means low pressure, which creates enough of a vacuum to pull out the documents. Watch them through your rearview mirror.
Hey, this is fun! Let's do more everyday science sometime soon. It's an interesting way to live.
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