Foundations of Physical ScienceWorkshop: Variations in the

Heating and Cooling of Earth

Key Question

What causes the seasons?

Two part InvestigationFirst ,we will measure how

variations in DISTANCE effect light intensity

Then, we will measure the light intensity at different PLACES on the globe

Light Intensity and Solar Energy Greater tilt angle spreads the light out over more area

More direct light = more energy/area = greater intensity

Areas with greater intensity will heat more

Developing a hypothesis about the seasons

Setting up your model of Earth’s orbit around the

sun The light represents the sun

Measure the light intensity with the solar cell and multimeter

Compare values

Measuring Light Intensity based on Distance

Four distances

A – 150 cm

B – 147 cm

C – 149 cm

D – 153 cm

Results

Position Distance from the sun (km)

Scale distance from the sun (cm)

Light intensity (mA)

A 150,000,000 150

B 147,000,000

C 149,000,000

D 153,000,000

Results

Position Distance from the sun (km)

Scale distance from the sun (cm)

Light intensity (mA)

A 150,000,000 150 1.02

B 147,000,000 147 1.09

C 149,000,000 149 1.07

D 153,000,000 153 0.98

How does Earth’s tilt affect the sun’s intensity?

How does Earth’s tilt affect the sun’s intensity?

Findings What role does axial tilt play in the intensity

of light on Earth?

At which position (A-D) and latitude does Earth receive the most light? The least light?

Which factor, distance or axial tilt, plays the most significant role in casing the seasons?

Was your hypothesis supported by your results?

Where is Summer in the Northern Hemisphere? (and

why) From position D to A is summer for the Northern Hemisphere

That is the segment of Earth’s orbit where the Northern Hemisphere is pointing at the sun and getting the most direct, and therefore most intense light