Question

procedure ii: apparent motion of the sun
use the 3 arcs drawn on the diagram of a plastic dome to answer the questions below. each line represents the suns path on a given day. the suns position at noon on each of those days is labeled as well.

1. a. based on the length of the lines, which date has the longest duration of insolation? (length of daylight)

b. based on the length of the lines, which date has the shortest duration of insolation?

1. according to the diagram of the plastic dome, is the sun ever located at our zenith (directly overhead) at noon in burnt hills?
2. according to the diagram of the plastic dome, which day or days did the sun rise directly in the east and set exactly in the west?
3. on which day is the angle of the noon sun the highest? the lowest?
4. describe the suns apparent diurnal motion in terms of its 1) path, 2) direction, and 3) rate of movement.

Explanation:

Step1: Analyze duration of insolation

The longer the arc - line representing the sun's path, the longer the duration of insolation. In the diagram, the June 21 arc is the longest.

Step2: Identify shortest duration

The shortest arc represents the shortest duration of insolation. The Dec 21 arc is the shortest.

Step3: Check zenith position

The sun is at the zenith when it is directly overhead. From the diagram, the sun's position at noon is not directly overhead (zenith) in Burnt Hills.

Step4: Determine equinox days

On the equinoxes (March 21 and September 21), the sun rises due - east and sets due - west.

Step5: Find highest and lowest noon - sun angles

The highest angle of the noon sun occurs on June 21, and the lowest on Dec 21.

Step6: Describe diurnal motion

1. Path: The sun's path is an arc across the sky. It is higher in the sky on June 21 and lower on Dec 21.
2. Direction: The sun appears to move from east to west across the sky.
3. Rate of movement: The sun appears to move at a relatively constant rate across the sky, completing a full arc in approximately 12 hours from sunrise to sunset.

Answer:

1. a. June 21

b. Dec 21

1. No
2. March 21 and September 21
3. June 21; Dec 21
4. 1) The sun's path is an arc across the sky, higher on June 21 and lower on Dec 21.
5. The sun moves from east to west.
6. The sun moves at a relatively constant rate, completing an arc in about 12 hours from sunrise to sunset.