Which has the most intense sunlight hitting it?

[shmijda]

Homework Statement

Which has the most intense sunlight hitting it?Question 2 options:
A point on the Equator at sunset

The North Pole at Noon on the Summer Solstace

Montreal at Noon on the Spring Equinox

The South Pole on the (Northern hemisphere) Summer Solstace

Homework Equations

none

The Attempt at a Solution

Ruled out first choice as it is at sunset.
Ruled out last choice as the South Pole does not receive much sunlight on the Summer Solstice
Stuck between choice 2 and 3.[/B]

 

[Bystander]

Stuck between choice 2 and 3.

What do you know about choices 2 & 3?

 

[Borek]

Homework Equations

none

That's where you went wrong. Intensity can be described numerically, and then applying what you know about the Sun position in each case is a key to the correct answer.

 

[shmijda]

That's where you went wrong. Intensity can be described numerically, and then applying what you know about the Sun position in each case is a key to the correct answer.

We were supposed to do this without looking at the intensity numerically, so how do I choose between 2 and 3?

 

[Bystander]

How far above the ecliptic plane are the two locations at the times of the year stated in the question?

 

[Borek]

We were supposed to do this without looking at the intensity numerically

You can't answer the question without comparing angles. Angles are numbers.

 

[vela]

We were supposed to do this without looking at the intensity numerically, so how do I choose between 2 and 3?

You don't need to calculate the intensities, but you can reason mathematically which situation results in more intense sunlight. What determines how intense the sunlight is at noon?

 

[shmijda]

You don't need to calculate the intensities, but you can reason mathematically which situation results in more intense sunlight. What determines how intense the sunlight is at noon?

The angle of incident rays? In this case I would say the north pole at noon

 

[Bystander]

 

[vela]

The angle of incident rays? In this case I would say the north pole at noon

Are you just guessing? What's the angle between the incident rays and the normal at the North Pole on the summer solstice? You should be able to figure this out knowing the tilt of the Earth and the fact that the North Pole is at 90 degrees latitude.

What about for Montreal on the vernal equinox? If your answer is right, the Sun should be lower in the sky than it was for the North Pole on the summer solstice. Can you justify that?

 

[shmijda]

for north pole on summer solstice - I got angle 66.6
for montreal on equinox - angle 45.5

 

[vela]

Those look reasonable, so the Sun is lower in the sky in...

 

[shmijda]

Those look reasonable, so the Sun is lower in the sky in...

Montreal, thus North pole at noon on summer solstice is right?

 

[vela]

Those angles are between the incident ray and the normal. Zero degrees would correspond to the Sun being directly overhead, and 90 degrees would be if the Sun were on the horizon.