7th Grade Science

December 5th 2012

Warm-up

• Your job is to find your old agree/disagree sheet (on the front desk ) and fill out the final column of whether you agree or disagree

Demonstration?

• If time allows….

Objective

• Predict the differences in temperature over time on different colored objects placed under the same heat source

Scenario

• You and your family decide to go to the local swimming pool for a day of swimming and fun. The car is parked in a nice shady spot when you leave it early in the morning but when you return, it is parked in the middle of full and direct sunlight. The seat covers in the car are black and the dashboard as well as other parts of the car are light grey. What part of the car is going to be the hottest? Why?

Thinking time…

• About 30 seconds to come up with an explanation

How thermal energy transfers..

• objects can absorb and reflect light• The color of an object depends on what kind of

light it reflects• For example, a green object reflects green light

and absorbs all the other visible colors of light. When we see a green object, we perceive it as green because it reflects the green wavelength of color back to our eyes

• We see green because it is what is reflected back

Darker objects and thermal energy

• Dark colored objects absorb light and thermal energy and light colored objects reflect light or thermal energy

• Light is converted to thermal energy and emits this as heat

• Black objects absorb more light and therefore emit more heat

For the rest of the class period

• Work on your study guide for your exam on Friday