Atmospheric refraction of light rays is responsible for which of the following effects? a. spherical aberration c. chromatic aberration b. mirages d. total internal reflection in a gemstone

b. mirages

Explanation:

A mirage is an optical illusion that occurs naturally due to refraction in the atmosphere. This phenomenon occurs especially in environments where the air exhibits large variations in its temperature, causing each of the layers with different temperatures to have a different index of refraction and therefore, the light rays will be diverted to the colder side.

Then, when this happens, displaced images of distant objects, or in the sky, are produced. In fact, sometimes it seems that distant objects are reflected on a liquid surface that is not real.

most voltage drop calculators want the distance between the source and destination. then internally, they double it so both the source and return wires are calculated. but you need to know which distance the calculator uses so you're not half of what you should be or double what you should be.

most circuit breakers will not take a #6 directly, so the electrician will have to splice on a smaller pigtail. you also have to upsize the grounding wire when you upsized the ungrounded (hot) wire (see note in 250.122). this will preclude using most cable assemblies, as a cable with #6 copper will most likely only have a #10 grounding conductor. you need a #6 grounding conductor if the circuit is 20a. a #8 cable is no better, as it will have a #10 grounding conductor too. but most 20a breakers will take a #8 directly.

in your related post, you didn't say what type of load this is. if it is a light or heater, voltage drop won't be a big issue. if this is a motor, the current needs are huge at startup and the voltage drop can pose a problem. if this is a motor, knowing if the motor is under much load during startup will answer the voltage drop effect (a saw is easier to start than a compressor).

true tan speed = ang vel x radius