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What must be the elevation of an observer in order that he may be able to see an object on the earth thirty miles away assuming earth's radius is 3956 mi and earth is smooth sphere?
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∙ 14y ago
You should really try to solve this yourself first, in order to maximize the value in doing that. If you read this solution, please understand each step before proceeding to the next step, otherwise the lesson will be lost to you.
To determine the required elevation of an observer in order that he may be able to see an object on the earth thirty miles away, assuming the earth's radius is 3956 mi and the earth is a smooth sphere, first draw the triangle involved.
This is a right triangle, where the hypotenuse is the radius of the earth plus the elevation of the observer. One side is the radius of the earth to the object. The other side is the line of sight distance from the observer to the object, which is greater than 30 miles. That line of sight is tangent to the earth's circumference, at the point of the object, so the angle of line of sight relative to the radius at the object is 90 degrees.
The angle at the center of the earth is 360 degrees times 30 miles divided by the circumference of the earth, 2 pi 3956, or 24856, which is an angle of 0.4345 degrees.
The hypotenuse of a right triangle with one angle of 0.4345 degrees and side of 3956 is 3956 divided by cosine 0.4345 degrees, or 3956.1138 miles.
Subtract the radius, 3956 miles, and you get 0.1138 miles, or 601 feet.
Not asked, but answered for completeness, is that the line of sight distance is hypotenuse times sine 0.4345 degrees, or 30.0005751 miles, or 3.04 feet more than 30 miles.
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∙ 14y ago
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How do you find the angle of depression?
The angle below horizontal that an observer must look to see an object that is lower than the observer. Note: The angle of depression is congruent to the angle of elevation (this assumes the object is close enough to the observer so that the horizontals for the observer and the object are effectively parallel; this would not be the case for an astronaut in orbit around the earth observing an object on the ground).
What is the angle of declination and how do you use it?
An angle of declination is relevant when an observer is at a higher altitude than the object being observed. It is the angle made by the line of sight with the horizontal. Suppose this is angle x. Then if the altitude of the observer is known to be h, then line-of-sight distance to the object is h*sin(x). The object is h*tan(x) from the point below the observer at the level of the object.Conversely, if the line-of-sight distance from the object to the observer or the horizontal distance to the point directly below the observer is known, it is possible to calculate the height of the observer.
What is the equation for height in physics?
Height of an object = (elevation of its top) - (elevation of its bottom)
Which type of objectives have angle of elevation?
The angle of elevation is looking at an object above your line of sight.
What is the object in angle of elevation and depression?
It can be any object that is above or below the horizontal from the perspective of a viewer.
How do you find the angle of depression?
The angle below horizontal that an observer must look to see an object that is lower than the observer. Note: The angle of depression is congruent to the angle of elevation (this assumes the object is close enough to the observer so that the horizontals for the observer and the object are effectively parallel; this would not be the case for an astronaut in orbit around the earth observing an object on the ground).
If you propel an object from ground level with a known trajectory and force and then propel the same object from a higher altitude with the same trajectory and force which object will travel further?
Assuming that in each case the object will not be acted on my any other force and that the object will not have to land at an elevation different from the elevation it left from, and assuming that the object will not encounter any obstacles-- the object will travel further if when launched from the higher altitude because it will encounter less gravity and less resistence from the air it travels through.
How is a UFO created?
When a strange object flies into the scope of an observer, and the observer is incapable of finding a suitable moniker for the object it is given the paradoxical identity of an Unidentifieed Flying Object.
How is the size of an object affected by its distance from an observer?
Its size is not affected in the least by its distance from an observer. If it were, can you possibly imagine thestress and strain on Brett Favre's body during a game, as he is watched by 60,000 people in the stands, allat different distances from him ? ! ?The object's APPARENT size ... i.e. the angle that it subtends at the eye of the observer ... depends onthe observer's distance from it, in the following totally predictable and purely geometrical fashion:The angle subtended by the object =arctangent [ (object's dimension perpendicular to the line of sight) divided by (observer's distance) ].But that's the observer's fault, not the object's.
What is the angle of declination and how do you use it?
An angle of declination is relevant when an observer is at a higher altitude than the object being observed. It is the angle made by the line of sight with the horizontal. Suppose this is angle x. Then if the altitude of the observer is known to be h, then line-of-sight distance to the object is h*sin(x). The object is h*tan(x) from the point below the observer at the level of the object.Conversely, if the line-of-sight distance from the object to the observer or the horizontal distance to the point directly below the observer is known, it is possible to calculate the height of the observer.
What is the difference between angle of Elevation and angle of Depression?
Angle of elevation is looking upwards to an object and angle of depression is looking downwards to an object
How does the geothermal energy reach earths surface?
Through convection. Since a hot object rises over a cold object (assuming they are the same object), the plastic rock in the mantle allows vents to bring up heat from deep within.
An object that is farther away than another object will have a parallax?
The farther an object is from the observer, the smaller its parallax is.
A red shift in the spectrum of the light from an object indicates the object is moving where?
away from the observer.
What is earths apparent motion?
I guess that would be an earthquake. But what do I know. I think it is though.
What is the equation for height in physics?
Height of an object = (elevation of its top) - (elevation of its bottom)
An object is in motion if it changes position relative t a?
Observer.
