Discover science and nature hobbies, from collecting insects and rocks to studying the stars as an amateur astronomer. Nature buffs can learn how to plan a whale watching trip, design a bird garden or discover how to best enjoy a trip to Yosemite. Have a taste for the strange and unusual? Explore the mystical world of the occult or learn to divine the future with fascinating astrology and numerology.
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Monocled cobras are familiar to many as the cobras who sway from the necks of baskets in time to a flute played by a snake charmer. Though snake charming was banned in 1991, humans still come in...
Concrete is a unique material in that it is very strong in compression, but extremely weak in tension. Cracks in some concrete surfaces occur not directly from compressive forces, but tensile...
You can calculate the revolutions per minute (rpm) of a circular object if you know its radius and how far it travels in a straight line in a given period of time. You may need to do some unit...
There are two methods for determining the best angle for solar panels: One for a static installation and one for a seasonally adjusted installation. A static installation means you will angle the...
The circumference of a circle is the length of the line that goes around it. You may need to find the circumference of a circle to solve a math or geometry problem, or for a real-life task such as...
Florida's precious salty waters are home to several protected species that are sensitive to over harvesting. To protect them, the state requires fisherman to purchase an extra permit in addition...
Using sunlight to heat outside air and deliver warmed air into your house through a window is a "green" way to reduce heating costs. The design is simple, and the materials are fairly inexpensive....
Resistors are made from conductors. Conductors are materials that electricity can travel through easily, such as iron, copper, and silver. Linear resistors are ohmic, which means they follow Ohm's...
Biometric devices are a relatively modern technology---in use during the latter half of the 20th century; however, massive development and common use of biometric identification systems really...
The coast redwood, Sequoia sempervirens, is the tallest species of tree in the world and the fastest growing conifer, or cone-bearing tree, in North America. The redwoods are not only the tallest...
Deoxyribonucleic acid (DNA) forensics testing precisely compares specific points in the sequence of DNA between two or more individuals. By choosing multiple points throughout the human genome...
Drive belts are flat, rubber loops used in various machines to rotate parts that the motor cannot rotate directly. In cars, a drive belt controls the power steering and other accessories. In a...
Animals naturally intrigue children, and learning about them is a favorite subject. When learning about animals, children also start to learn about themselves. They notice similar features such as...
Important to engineers and meteorologists alike, the field of psychrometrics explores the thermodynamic properties of gas-liquid mixtures, including air and water vapor. The particular...
A flood frequency curve is a valuable tool to extrapolate how often a flood of a given discharge will occur. A flood frequency curve can be constructed by plotting a graph of discharge versus...
A lead-acid battery is a source of direct-current (DC) electricity. When the battery begins to lose its charge, it must be recharged with another DC source. An electric motor, though, is as an...
Coral reefs house a variety of different animal and plant species in the ocean. Though abundant in life, reefs do not have the nutrients needed to house seaweed in particular, but lately it has...
In ecologically terms, an organism is adapted to its ecosystem if it can tolerate the local conditions long enough to produce fertile offspring. This result is a measure of ecological success....
The river otter is a member of the weasel family that inhabits parts of North America. This mammal ranges from the Deep South and up the Atlantic Coast into states such as Virginia and Maryland....
Sometimes referred to as "variable speed," a variable frequency drive (VFD) controls the rotational speed of a single-phase or three-phase AC inductor motor by altering the frequency of the...
Convex mirrors have a variety of uses today---many of which are for security purposes, as well as to help drivers on the road. These mirrors offer several distinct advantages, as well as...
A weather RADAR is a type of radar that detects clouds and precipitation in the atmosphere. Weather radars are used to locate and identify precipitation such as rain and snow, and have also been...
Bridge diodes are rectifiers. Rectifiers are used to convert alternating current (AC) signals to that of direct current (DC). They are also known as full-wave bridge rectifiers because they are...
Scuba diving is a fun and educational hobby. As it involves being submerged for long periods, it requires equipment that must function properly to ensure your safety. The air regulator is vital as...
Mixing bird seed with suet, or raw beef fat, not only attracts pretty birds to your backyard and provides them with nutrition all year round, it is a fun and educational activity. You can mix bird...
Deceleration is simply acceleration working in the opposite direction to an object's velocity, causing it to slow down. There are several equations in mechanics that relate acceleration to...
The pH of a substance is a measure of its hydrogen ion activity which determines whether it is acidic, neutral or alkaline. Digital pH meters measure and display the pH of liquids and semi-solids....
Atomic clocks work by reading a special radio signal; the clock reads the time contained in the signal, generated in the United States by the National Institute of Standards and Technology, and...
Filtering water is an essential part of maintaining a healthy body. Numerous commercial filters are available that can be fitted at home, but simple filtration devices can be made from common...
Many different types of molds, a type of fungus, grow on many different types of food. Fruits, vegetables, breads, cheese, beef and poultry products, jams and jellies among many other types of...
In chemical reactions catalyzed by an enzyme, the enzyme lowers the amount of activation energy required by temporarily bonding with the substrate and twisting it into a strained state. The...
Magnetism and electricity are intimately related. A magnet can induce electrical current and an electrical current induces magnetism. When electrons flow through a wire (electricity), a magnetic...
The process involved in reversing the poles of a magnet depends upon whether the magnet is an electromagnet or a permanent magnet. An electromagnet is a temporary magnet powered by electricity....
While methane (CH4) is the gas most commonly associated with flatulence and swamp gas, it is hydrogen sulfide (H2S) that provides the stench. The human olfactory system (i.e. the nose) is...
The light that is emitted from a laser is more intense than the light that comes from an incandescent bulb. You can convert a flashlight into a laser pointer by purchasing a few parts from a hobby...
Concerns about the whooping crane sparked the 1966 creation of the Endangered Species Preservation Act. The act was the second bill passed in the 20th century to protect and preserve wildlife and...