EXPERIMENT 10.3

INFRARED LIGHT

STUDENT INFORMATION

Name:

Date:

Email:

Teacher's Email:

PURPOSE:

To investigate the properties of infrared light and understand how it transfers heat energy.

BACKGROUND:

Infrared (IR) light is a type of electromagnetic radiation with wavelengths longer than visible light but shorter than microwaves. Though invisible to the human eye, we can feel infrared radiation as heat. The sun emits a significant amount of infrared radiation, which warms the Earth's surface. Many everyday objects emit infrared radiation, with warmer objects emitting more than cooler ones.

Infrared light is used in various applications, including thermal imaging cameras, remote controls, night vision equipment, and heat lamps. In this experiment, we will explore how infrared radiation transfers heat and how different materials interact with infrared light.

MATERIALS:

Two identical thermometers
Two identical glass jars with lids
Black construction paper
White construction paper
Scissors
Tape
Sunny location or heat lamp
Timer or stopwatch
Optional: Infrared thermometer
Optional: Remote control and digital camera or smartphone

SAFETY PRECAUTIONS:

Be careful when handling glass jars
If using a heat lamp, do not touch it when hot
Do not look directly at the sun
Use caution with scissors

PROCEDURE:

Part 1: Absorption of Infrared Light

Cut two circles from the construction paper—one black and one white—that are large enough to line the bottom of the jars.
Place the black paper circle at the bottom of one jar and the white paper circle at the bottom of the other jar.
Place one thermometer in each jar and secure the lids.
Record the initial temperature in both jars.
Place both jars in direct sunlight or under a heat lamp, ensuring they receive equal exposure.
Record the temperature in each jar every 5 minutes for 30 minutes.
Graph your results, with time on the x-axis and temperature on the y-axis.

Part 2: Detecting Infrared Light (Optional)

In a darkened room, point a remote control at a digital camera or smartphone camera.
Press buttons on the remote control while looking at the camera screen.
Observe and record what you see on the camera screen when you press the remote control buttons.
If available, use an infrared thermometer to measure the temperature of various objects in the room. Compare these readings with how the objects feel to the touch.

DATA COLLECTION:

Part 1: Temperature Measurements

Time (minutes)	Temperature in Jar with Black Paper (°C)	Temperature in Jar with White Paper (°C)	Temperature Difference (°C)
0 (Initial)			-
5			-
10			-
15			-
20			-
25			-
30			-

Part 2: Infrared Detection Observations

What did you observe on the camera screen when pressing the remote control buttons?

If you used an infrared thermometer, record your measurements and observations:

ANALYSIS QUESTIONS:

1. Which jar showed a greater temperature increase? Explain why this occurred in terms of absorption and reflection of infrared light.

2. How does the color of an object affect its ability to absorb infrared radiation? Provide examples from your experiment.

3. If you conducted the remote control observation, explain how the digital camera was able to detect the infrared light when your eyes could not.

4. Describe three real-world applications of infrared technology and explain how they work.

5. How is the greenhouse effect related to infrared radiation? Explain the connection between this experiment and global warming.

CONCLUSION:

Summarize what you learned about infrared light from this experiment. Include your key findings and how they relate to the properties of infrared radiation.

SUBMIT YOUR RESULTS:

Click the button below to submit your experiment results to your teacher.