Science

Refine Search

Does Best Buy take old TVs for disposal as e-waste?

While the specific details vary by location and state, most stores accept tube televisions with screen sizes of 32 inches or less, projectors, LCD televisions with screen sizes of less than 60 inches, and portable televisions for recycling. The program typically does not accept front- or rear-projection televisions, any device with exposed cathode ray tubes, or tube televisions with screen sizes larger than 32 inches.

Continue Reading

What do interstitial cells do?

The Encyclopedia Britannica states that testosterone is a hormone that develops male sex organs and produces masculine qualities. Puberty is the term used to describe the body’s gradual development of secondary sexual characteristics. Puberty in males begins when certain hormones become active within the brain and travel to reproductive organs.\nHormones such as the luteinizing hormone or LH, gonadotropin release hormone or GnRH and testosterone are all regulated by the endocrine system. Spermatogenesis starts when the hypothalamus secretes GnRH causing the release of LH. The LH binds to spe..

Continue Reading

What causes a hurricane to form?

Hurricanes rarely form unless the warm water they need is abundant, at least 80 degrees Fahrenheit and surrounded by still air or calm wind blowing in a consistent direction. For this reason, they always form over warm ocean waters in tropical areas. The warming and rising process leaves a low pressure area. When the low pressure area hits a certain size and pressure level, meteorologists refer to it as a "tropical depression," the first stage toward becoming a hurricane. In order for the hurricane to form, however, the pressure must drop still more as warm air rises faster, displacing more co..

Continue Reading

How do you make an AC generator?

Factors affecting the amount of AC current the generator produces include the strength of the magnet, the length of the wire in the coil and the speed at which the magnets turn. A hand-crank egg beater drill is ideal for turning the magnets with this generator, as it's fast enough to light the lamp; an electric drill is another option. Even with the drill, the generator only produces enough power for the small lamp and not enough to light a flashlight bulb.\nThe output of this generator is a maximum of 2 volts, which is not enough to cause an electric shock. However, it may exceed the vol..

Continue Reading

What are the uses of a test tube rack?

Using glass has many advantages in a scientific environment, as glass can be sterilized, is easily cleaned, allows for easy viewing of the tube's contents, is non-reactive to many common chemical reagents and conducts heat evenly. However, glass is also very prone to breaking under sudden shocks, such as a drop off the lab table. In addition, test tubes are completely round and lack handles. Test tubes often do not even have flat bottoms, so it is impossible to rest them upon a table top as you would a cup. The roundness is to prevent mass loss when transferring materials from one contain..

Continue Reading

What are some benefits of using a spray dryer?

The heat and mass transfer during drying occurs in the air as vapor films surround the droplet. This protective envelope of vapor keeps the particle at the saturation temperature. As long as the particle does not become completely dry, evaporation takes place and the temperature of the solids does not approach the dryer outlet temperature. The surface area produced by atomization of the liquid feed allows a short gas residence time, ranging from three to 40 seconds depending upon the application, which permits spray drying without thermal degradation. This allows for fast turn-around times.\nT..

Continue Reading

What are the major muscles in the body?

The two major arm muscles are the biceps, which are at the front of the upper arm, and the triceps, which are at the back of the upper arm. They are most useful in lifting and pushing motions. The deltoids, located nearby at the top of the shoulder, also help with lifting motions, particularly for overhead lifting. The muscles used for properly sitting up straight are the latissimus dorsi, in the mid-back area; rhomboids, the muscles between the shoulder blades; the erector spinae, forming the lower back; and the abdominal muscles, covering the stomach area. Abdominal muscles are exercised pri..

Continue Reading

What kind of rocks are on the moon?

In many ways, lunar rocks resemble Earth rocks, giving credence to the theory that the moon was broken off of the Earth by a massive impact event early in the planet's history. However, moon rocks tend to have fewer volatile compounds and none of the hydrated minerals common in mineral deposits on Earth. Moon rocks are high in iron content, and some have substantial amounts of titanium. Regolith can contain fragments of the other three types of moon rock as well as other loose minerals.\nIn total, the Apollo missions brought back approximately 842 pounds of rocks from the moon for study. ..

Continue Reading

What is another name for prokaryotic cells?

Prokaryotic cells are simple molecules surrounded by a membrane and cell wall, but they lack more complex elements of more advanced cells, such as organelles. Prokaryotes come in round, rod or helical shapes, known as cocci, baccilli, and spirilla or spirochetes, respectively. Prokaryotes have genetic information in either nucleolids or circular loops called plasmids. The kingdom of Monera refers to simple bacteria, and most prokaryotes are bacteria; Archaea are types of bacteria that survive in harsh environments. Archaea are found in extreme environments, and they consist of methanogens, hal..

Continue Reading

Is gold a metal nonmetal or metalloid?

In nature, many compounds, such as tellurium, calcite and quartz, contain gold. Gold also can occur freely in nature. It is a malleable, shiny and soft metal that has the chemical symbol Au. Malleable means that it is easy to hammer or beat gold into thin sheets or thin wire. \nSome other physical properties of gold are that it is a conductor of electricity and heat, and it has a melting point of 1064.18 degrees Celsius. It also has good reflectivity properties. \nPresently, gold has many uses, including for jewelry, electrical contacts, printed circuits, shielding on space vehicles and denta..

Continue Reading
Showing 2571 to 2580 of 10000 (1000 Pages)