Calculate the sunrise and sunset local horizon points, Physics

This problem examines the seasonal solar radiation budget at three geographical locations: the Equator, 40º North, and 80º North.

2423_Calculate the sunrise and sunset local horizon points.png

NOTES: At a given geographical location, N, S, E, and W are the north, south, east and west points of the local horizon (also called "cardinal points" different from the same term applied to the precession of the equinoxes discussed in this course), O=observer on Earth, NP=celestial north pole, Z=zenith, X=location of sun at some instant, z=distance XZ to zenith, A=altitude of the sun (π/2-z), δ=declination of sun DX, which currently varies between ± 23.5º throughout the year, α=azimuth of sun; H=hour angle of sun measured from the meridian. During the day, the sun's rays strike the Earth's surface through a series of positive-valued angles A = 0o to a maximum Amax at meridian transit, and back to 0o. The vertical component, sinA is the "effective heating force." This is also expressed as zenith distance z = 90o-A.  From spherical geometry: cosz = sinθsinδ + cosθcosδcosH. To calculate the total time that the sun is in the sky, set z = 90o (sunrise at the East horizon) to get: cosH = -tanθtanδ. Solve for H and divide by 15 o per hour (the Earth rotates 15 o per hour) to convert to time for the morning half of the day.  Azimuth angles α of the rising and setting Sun are calculated from the formula: cosα = sinδ/cosθ. 

For the summer and winter solstices, and spring (or fall) equinox of each location:

 (A) Calculate the sunrise and sunset local horizon points (+α) in degrees from due North (note: west = negative, east=positive).

 (B) Calculate the length of the day in hours, minutes, seconds.

 (C) Using the solar constant So=1370 W/m2 , calculate the 'effective heating force' that reaches the top of the atmosphere per hour; plot these amounts on a graph of W/m2  vs. hour of the day. What is the summer/winter ratio of total daily insolation at each location? How does the total daily insolation at summer solstice compare among the three locations?

Posted Date: 2/21/2013 3:15:20 AM | Location : United States







Related Discussions:- Calculate the sunrise and sunset local horizon points, Assignment Help, Ask Question on Calculate the sunrise and sunset local horizon points, Get Answer, Expert's Help, Calculate the sunrise and sunset local horizon points Discussions

Write discussion on Calculate the sunrise and sunset local horizon points
Your posts are moderated
Related Questions
Determine the Shear Force in kN rounded to 1 DP and Bending Moment in kN.m rounded to 1 DP at point C in the beam when the UDL for AC on the beam is P52 kN/m and the maximum value

A bullet with mass m is fired into a block of a mass M intially at rest at the edge of a frictionless table of a given height. the bullet remains in the block, and after the impact

It is the ratio of the internal electric field induced by the charges on the surface on the dielectric when an external field applied to the polarization of the dielectric.

Lambert's laws (J.H. Lambert): Lambert's first law The illuminance on a surface illuminated through light falling onto it perpendicularly from a point source is propor

sensitivity of moving coil galvanometer can be increased by decreasing?

a) Formation of domains b) On the basis of domains formed c) These are strongly attracted in an external magnetic field i.e. they easily go from low to high field region d

Circuits involving capacitive decay: Consider the circuit shown below. Depending on the time constant of the circuit, relative to the period of the square wave applied to it,

What are the design constraints of slide emitting optics? The genuine illuminance of side emitting optics is low, while the luminance is quite acceptable in many cases. This m

Define Entropy of Ideal Gas? A vessel of volume V 1 contains N molecules of an ideal gas held at temperature T and pressure P 1. The energy of a molecule may be written in t

does lights of different wavelengths help us to see different colour