Science

Refine Search

Which gas is used in light bulbs?

The gases used in light bulbs are known as inert gases. An inert gas is non-reactive and extremely resistant to chemical change. Inert gases can either be elements or compounds. Due to their inherent stability, inert gases such as argon and nitrogen do not allow a filament to catch fire in a light bulb. Other examples of usage of an inert gas include packing food with nitrogen to prevent spoilage and storing historical documents under argon to resist degradation.

Continue Reading

How loud is 80 decibels?

Decibels are used to measure the intensity of sound on a logarithmic scale. For every increase of 10 decibels, the sound is considered to be twice as loud. Another way to imagine the intensity of 80 decibels is twice the volume of a normal conversation. The average person's pain threshold is 110 decibels, the sound level of a live rock concert, and eardrums can immediately rupture when exposed to 150 decibels, the sound level of a jet engine or top fuel race car. For an amplifier to raise the intensity of sound by 10 decibels, it requires 10 times more wattage.

Continue Reading

How many muscles are used to chew food?

Chewing muscles can be further classified as deep and superfificial muscles of mastication. The deep muscles are the temporalis and the deep masseter. They are so called because they are partially hidden by bone. These two muscles work to pull the mandible up towards the maxillae when you chew.\nThe superficial muscles of mastication are the lateral pterygoid, the medial pterygoid and the superficial masseter. The superficial masseter is responsible for raising the mandible against the maxillae with force, and the medial pterygoid and the lateral pterygoid draw the mandible forward.

Continue Reading

What is the shape of a DNA molecule?

DNA molecules contain all the genetic information that is passed down from parents to their offspring. The four bases are arranged in certain ways, and these determine what information is inherited. Adenine is always paired with thymine, while guanine and cytosine always match up to one another. The specific order of these bases along the ladder makes each organism an individual. Most of an organism's DNA is located in the nucleus of its cells.

Continue Reading

What are similarities between vertebrates and invertebrates?

Vertebrate animals and a few invertebrates within the phylum Chordata all exhibit the characteristics of chordates, which include: possession of notochord, bilateral symmetry, segmented body, pharyngeal pouches at some developmental stage and a complete digestive system. They also possess ventral heart, closed blood system and a tail at some stage of life. A few invertebrates like sea squirts are similar to vertebrates, and grow flexible rods known as notochords as embryos. The notochord develops into the vertebral column in vertebrate animals.\nThe cells of both vertebrates and invertebrates..

Continue Reading

How many grams are in 1 newton?

An object's mass is different from its weight. Mass pertains to the amount of material in a substance while weight measures the force a certain mass exerts due to gravitational force, which is equal to 9.8 m/s2. The base unit for mass in the international system of units is kilogram while the standard unit for force is newton. One newton can be expressed in kilogram-force, which is roughly equivalent to 0.012. Since 1 gram is defined as 1/1,000th of a kilogram, 1 newton is approximately equal to 102 gram-force. Based on the United States customary system, 1 newton is also equivalent to 0...

Continue Reading

Which cell junction forms an impermeable barrier?

Cell junctions fall into one of three categories: communicating junctions, impermeable junctions and adhering junctions. Classification of these junctions depends on their function. Communicating junctions assist in the exchange of small molecules from one cell to another. These include chemical synapses and cell junctions. Adhering junctions assist in keeping cells together. These include belt desmosomes, spot desmosomes and hemidesmosomes.

Continue Reading

How do you find the number of neutrons in an atom?

Get a periodic table of elementsPeriodic tables are found online and in chemistry textbooks. They list every known element and provide the number of protons and atomic masses for each element. Find the element's atomic numberThe atomic number is located above the element symbols. This is the number of protons found in one atom of the element. Find the element's atomic massThe atomic mass is listed beneath the element symbols. This is the sum of the protons and neutrons found in one atom of the element. It is an average of all possible isotopes, so, round the value to the nearest whol..

Continue Reading

What makes aluminum foil a good insulator?

Because of its excellence as an insulator, aluminum foil is a common surface with radiant barriers. Holding up a piece of aluminum foil in front of one's face shows these properties. After a short amount of time, one feels heat bouncing back toward his face. This is the heat energy from the person's body bouncing back from the foil. The human face has an absorption rate of 99 percent for infrared rays (far more than the 5 percent of foil). As a result, the person feels heat coming back from the foil.\nConstruction engineers use aluminum and aluminum foil to manage heat effectively. B..

Continue Reading

Who discovered retrograde motion?

Although Ptolemy's model of the solar system has since been discredited, the idea of retrograde motion is still widely used in astronomy. The modern use of the term "retrograde motion" refers to a celestial body's tendency to move in the opposite direction of other bodies in its system, such as the seven planets' movements and orbits in relation to the sun or their own moons.

Continue Reading
Showing 8811 to 8820 of 10000 (1000 Pages)