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Why do compound microscopes invert the images?

The inverted image is made from a positive lens, which means the image formed after light passes through the lens is a real image. This real image is inverted at the focal length. An example of this is using a letter of the alphabet. When the letter "e" is put right-side up in the slide to the observer, it is projected upside down in the tube. Moving the slide to the right shifts the image to the left, and vice versa.\nA compound microscope is so called because there are multiple lenses magnifying images. Underneath the slide is a light source, then the stage upon which the slide sits. The ima..

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What are the benefits of a bilateral knee replacement?

There are two forms of bilateral knee replacement, notes the Rothman Institute. The first, simultaneous bilateral knee replacement, involves one surgical event and a single rehabilitation period. The result is a shorter hospital stay and the associated lower costs. However, this procedure is only recommended for patients in good health because of the stress it places on the cardiovascular system. Another disadvantage of the procedure is that the initial rehabilitation periods are more strenuous because both legs are incapacitated.\nStaged bilateral knee replacement surgery, on the other hand, ..

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How do you use sone units to compare loudness?

A decibel is a measure of sound intensity. The phon is a unit that measures loudness, taking into account the frequency of a sound in addition to the intensity. If a sound is as loud as a 60-decibel sound at a standard frequency of 1000 Hz, it is defined to have a loudness of 60 phons. To determine the loudness of a complex sound, scientists compare it to a 1000-Hz test tone using filter contours to approximate the human ear.\nSince the phon is based on the decibel, it is a logarithmic unit. In 1936, Stanley Smith Steven created the sone scale to provide a measurement that was directly proport..

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How is coal used today?

Coal is primarily used in modern times to boil water and produce steam, which is in turn used to spin generator turbines for electricity generation. Nearly two-thirds of the coal recovered is now used in coal-fired power plants around the world. Coal is also used in the steel manufacturing process, which utilizes coke, a by-product of burning coal. Some structures and industrial installations still use coal for heating the actual structure, though these are becoming quite rare. Most modern industrial uses for coal, outside of electricity production, involve large coal-fired furnaces.\nCoal has..

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How do you convert 1,500 lumens to watts?

Determine the luminous efficacy of the light sourceEach light source (LEDs, halogen lamps, etc.) has a fixed luminous efficacy. Identify the kind of electric light used, and then find the luminous efficacy using a table. Insert figures into the formulaThe data points should then be inserted into the formula: Watts = lumens / luminous efficacy. Complete the calculation Divide 1500 lumens by the luminous efficacy figure of the light in question with a calculator to determine the answer in this case.

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How is the mass number calculated for an element?

Find the number of protonsUsing the periodic table of elements, find the atomic number of the element with mass numbers that need to be calculated. The atomic number of an element is equivalent to its number of protons. For example, the atomic number of sodium is 11. Thus, its number of protons is 11.Find the number of neutronsTo find the number of neutrons, use the periodic table of elements again. This time, find the element's atomic weight, and round it to the nearest whole number. Subtract the number of protons from the atomic weight. The result is the number of neutrons. Therefore, t..

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What is a first-class lever?

Levers are simple machines — apparatuses composed of few or no moving parts that make performing a task easier by one or more of four methods:\n\nTransferring where the force is applied to where it acts\nChanging the distance over which the force is applied or the speed with which it is applied\nChanging the direction of the applied force to that of the acting force\nIncreasing the magnitude of the acting force over that of the applied force\n\n\n \nThere are three classes of levers, based on the arrangement of the load, the fulcrum and the location where the force is applied:\n\nFirst-class..

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What is the air pressure in the exosphere?

The exosphere reaches altitudes of 6,200 miles and is connected to outer space. While most molecules in the exosphere are eventually pulled back into the lower layers of the atmosphere by gravity, some particles are released into outer space due to the extremely low gravity and pressure. Molecules in the exosphere typically do not come into contact with each other and move along arcing trajectories before cycling throughout the atmospheric layers.

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What are the functions of the left and right brain?

Through the work of Roger W. Sperry in 1981, the right brain-left brain theory originated during studies on patients who suffered strokes. Patients experiencing strokes on the right side of the body had damage to the left side of the brain, and those with diminished function on the left side of the body had injuries on the right side of the brain. Although the treatment involved separating the two halves of the brain, studies show that both halves work best when they work together, communicating through the corpus collosum, according to About.com.\nThrough the right brain-left brain theory, pe..

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What are the characteristics of the exosphere?

Most satellites, including the International Space Station, orbit immediately below or within the exosphere. The exosphere is also the layer where molecules and atoms escape into deep space. The immediate layer before the exosphere is the thermosphere and the boundary that separates the two is known as the thermopause, which is about 375 miles above Earth. Atoms and molecules of atmospheric gases below the exosphere are often in constant collision with each other, but the molecules within the exosphere rarely collide because they are usually hundreds of miles apart. However, despite the huge d..

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