• The Conservation Law of Energy states that energy may neither be created nor destroyed. In other words, the sum of all the energies doesn’t change; it’s a constant.
Exercise
• Getting 30 minutes or more of daily exercise can:
• Improve your overall mood.
• Improve your body’s ability to use insulin.
• Lower blood pressure.
• Lower “bad” LDL and raise your “good” HDL. [See Cholesterol.]
• Reduce stress.
• Decrease fatigue.
• Strengthen your heart.
• Improve muscle tone and strength.
• Decrease body fat.
• Increase energy levels.
• Reduce your risk for heart disease, high cholesterol, diabetes, high blood pressure, and colon cancer.
• Help control weight.
• Help build and maintain healthy bones, muscles, and joints.
• Help relieve symptoms of anxiety and depression.
• Increase life expectancy.
• Increase overall quality of life.
• The five worst floods in history all occurred in China. These include the 1975 flood in the Hong and Ru rivers; the 1642 flood in the Yellow River; the 1938 flood in the Yellow River; the 1887 flood in the Yellow River; and the 1931 flood in the Yellow River—the worst flood in history. This flood left more than 80 million people homeless, flooded 42,000 square miles (108,880 km2) of land, and had a death toll of between 850,000 to four million.
• It is has been hypothesized that the Great Biblical flood known as Noah’s Ark occurred when the Mediterranean broke through the Bosporus Straits and flooded the Black Sea, circa 5600 BC.
• In the United States, more than half of all fatalities during floods are auto-related, usually the result of drivers misjudging the depth of water on a road and the force of moving water.
• A car can float in just a few inches of water; just 6 inches (15 cm) of water will reach the bottom of most passenger cars and cause loss of control and possible stalling. Two feet (0.6 m) of rushing water can carry away most vehicles, including sport utility vehicles (SUVs) and pickups.
• Flash floods are the number-one weather-related killer in the U.S.
• The principal causes of floods in the Eastern United States and the Gulf Coast are hurricanes and storms; the principal causes of floods in the Western United States are snowmelt and rainstorms.
Flowers
(Largest and Smallest)
• Largest bloom in world:
• Perhaps best known for its bloom smelling like rotting meat, the Rafflesia arnoldii is the largest bloom in the world.
• Found in the rain forests of Indonesia, Rafflesia arnoldii can grow to be 3 feet (0.91 m) across and weigh up to 15 pounds (6.8 kg)!
• A parasitic plant with no visible leaves, roots, or stem, the Rafflesia arnoldii attaches itself to a host plant to obtain the water and nutrients it needs to survive.
• The Rafflesia’s bloom, which only lasts around five to seven days, emits a repulsive scent to attract insects for the purpose of pollination.
• Smallest bloom in the world:
• Imagine one itty-bitty candy sprinkle! That’s the size of an entire watermeal plant!
• A member of the Lemnaceae family, the watermeal plant (Wolffia globosa) averages 1/42 of an inch long and 1/85 of an inch wide.
• Okay, I really want you to understand how small I’m talking. Ready? The entire plant weighs about 1/190,000 of an ounce—the same as two grains of table salt! If you tried to fill a thimble with them, you’d need about 5000 plants! If you were to find this rootless plant that happily floats on freshwater lakes and in marshes, you’d think someone had spilled cornmeal!
• The flower of the Wolffia has single pistil and stamen and thus, not surprisingly, it also produces the world’s smallest fruit, called a utricle.
Four Forces of Flight
• The four forces of flight are weight, lift, thrust, and drag. These forces make an object move up and down, fast and slow. The amount of each force compared to its opposing force determines how an object moves through the air.
• Weight is the downward force that an aircraft must overcome to fly. Weight is the amount of gravity multiplied by the mass of an object.
• Lift is the opposite force of weight. For an aircraft to move upward, it has to have more lift than weight. Thus, lift is the push that lets something move up.
• Drag is a force that pulls back on something trying to move. The shape of an object also affects drag. Generally speaking, round surfaces usually have less drag than flat ones, and narrow surfaces usually have less drag than wide ones. The existence of drag explains why airplane wings are curved on top and flatter on the bottom. That shape makes air flow over the top faster than under the bottom. As a result, less air pressure is on top of the wing. This lower pressure makes the wing—and the airplane—able to move upward.
• Thrust is the opposite force of drag—it’s the push that moves something forward. For an aircraft to keep moving forward, it must have more thrust than drag. A small airplane might get its thrust from a propeller; a larger airplane might get its thrust from jet engines; a glider doesn’t have thrust and only flies until the drag causes it to slow down and land.
Freezer Burn
• When perfectly good food becomes discolored, parched, frost-covered, and/or has leathery dry spots following a long period in the freezer, we say the food is “freezer-burned.” What happened to cause this?
• The freezing process transforms the water molecules within foods to form ice crystals, which is fine because that’s how the preservation method works. Here’s the thing: Water molecules are drawn to the most hospitable environment, which is the coldest place they can find—the sides of your freezer! It’s that migration of water molecules that causes the food to become dehydrated, or freezer-burned.
• Oxygen molecules can also seep into frozen foods, particularly when the food isn’t wrapped tightly enough, which dull the color and modifies, or even ruins, the food’s flavor.
• Freezer burn is far more likely to occur if the temperature in your freezer fluctuates above 0°F (-17.7°C). This typically occurs when people keep opening and closing the freezer. The standard temperature setting for freezers is usually -10 to 0°F (-23 to -17.7°C).
• And just for the record, there is a limit as to how long foods can be safely frozen. Sooner or later the water molecules will find their way out of the frozen food to a colder place in your freezer.
• And a few quick tips:
• The faster a food freezes, the better, as this minimizes those