Science
Strand IV
Use Scientific Knowledge from the Physical Sciences in Real-World Contexts

 

Science/Strand IV
Content Standard 4
All students will describe sounds and sound waves; explain shadows, color, and other light phenomena; measure and describe vibrations and waves; and explain how waves and vibrations transfer energy. (Waves and Vibrations)

 

Science/Strand IV/Content Standard 4
Middle School

 

Science/Strand IV/Content Standard 4/Middle School
Benchmark 3
Explain how light is required to see objects.

Benchmark Clarification

When an object reflects light waves it is said to be illuminated. In order to see these objects, the light waves travel in a straight path and are received by the eye. A red sheet of paper appears red because red light is reflected off the paper, while all other colored light (orange, yellow, green, blue, indigo, violet) is absorbed by the paper. An object can be seen because of emitted or reflected light. In a “perfectly dark” room, an object cannot be seen because no light is reflected.

Students will:

  • Demonstrate an understanding of how light is required to see objects

Key Concept / Real World Context / Instructional Example / Assessment Example / Resources

 

Science/Strand IV/Content Standard 4/Middle School/Benchmark 3
Key Concept

  • light source
  • object
  • eye as detector
  • illumination
  • path of light
  • reflection
  • absorption

 

Science/Strand IV/Content Standard 4/Middle School/Benchmark 3
Real World Context

  • seeing common objects in our environment
  • seeing “through” transparent media:
    • windows
    • water
  • using flashlights to see in the dark

 

Science/Strand IV/Content Standard 4/Middle School/Benchmark 3
Instructional Example

Benchmark Question: How is light required to see objects?

Focus Question: What must happen to light in order for a person or other animal to see objects?

Students will discuss the following situations:

Coal miners wear helmets with lights. Why is the light necessary for the job?

Sometimes it is easy to see at night; sometimes it is not. Why?

Students will work in small groups and conduct the following investigations that answer the question, “What must happen to light in order for a person or other animal to see light?” Each student will write a hypothesis before beginning the investigation.

1. Cut a 6.0 cm (2.5 inch) square door in one side of a shoebox.

A. Cut a peep hole in the other end of the shoebox..

B. With the door closed, students should describe what they see.

C. With the door open, students should describe what they see .

D. Put a small object in the box..

E. Have one student open and close the door while another discovers what is in the box.

Through repetition, students will discover that they can see only when light is present.

Students will write answers to the following questions:

  • What do you see when the door is closed?
  • What do you see when the door is open?
  • Why is there is a difference between the first and second question above?

(Extension: Have students use colored filters or cellophane and observe results.)

Constructing: (SCI.I.1.MS.1).

Reflecting: (SCI.II.1.MS.3).

 

Science/Strand IV/Content Standard 4/Middle School/Benchmark 3
Assessment Example

Students will work in small groups and conduct the following investigation to answer the question, “Which color paper reflects light the best?”

A. As seen in the diagram, a white screen (made of white cardboard or paper) should be placed on the table at an angle.

In a darkened room:

B. Observe how a black sheet of paper reflects light by shining a flashlight on a piece of black construction paper lying flat on the table.

C. Observe how a white sheet of paper reflects light by shining a flashlight on a piece of white construction paper lying flat on the table.

D. Students should repeat this procedure with different colored sheets of paper.

Students will record their results in lab reports and answer the following questions:

1. Which color light reflects the most light?

2. Which color paper reflects the least light?

3. What must happen to light in order for a human to see an object (describe the path)?

NOTE: If you were to replace the screen in the diagram with an observer, this activity would explain correctly how the reflection of light off an object results in the observer’s ability to see that object.

(Give students rubric before activity.)

Scoring Rubric

Criteria

Apprentice

Basic

Meets

Exceeds

Accuracy of explanation

Identifies white as brightest and black as dimmest but gives only partial explanation.

Identifies white as brightest and black as dimmest but only explains one of them.

Identifies white as brightest because it reflects more light and black as dimmest because it reflects a little light and absorbs most.

Identifies white as brightest and black as dimmest with a correct explanation and describes the image on the screen as diffused and explains why.

Accuracy of description — path of light

Identifies few parts of the path of light needed to see an object and uses few key terms correctly.

Identifies some part of the path of light needed to see an object and uses some key terms correctly.

Identifies all parts of the path of light needed to see an object and uses many key terms correctly.

Identifies all parts of the path of light to see an object and uses all key terms correctly.

 

Science/Strand IV/Content Standard 4/Middle School/Benchmark 3
Resources

Webliography.
http://mtn.merit.edu/mcf/SCI.IV.4.MS.3.html

Gore, Gordon. Light & Colour. EXPERIMENTING WITH…SERIES. Trifolium Books, 2001.