University:
University of Missouri-Kansas City
Course:
PHY-SCI 110 | Foundations Of Physical Sciences I
Academic year:

2023
Views:

34

Pages:

3
Author:

tantntb1

Student Exploration: Radiation Prior Knowledge Questions (Do these BEFORE using the Gizmo.) 1. The Sun is millions of kilometers away. How can heat from the Sun get here? The Sun's energy gets to the Earth through radiation, which you can prove just by standing outside and letting the sun's rays warm your face on a sunny day 2. If you look inside an electric stove or toaster oven, how can you tell whether it’s turned on? The burner or heater is glowing red and radiating heat Gizmo Warm-up In the Radiation GizmoTM, you can focus the light of a superpowerful flashlight upon a kernel of popcorn and see what happens. The lens, which focuses the light, can be moved to the left or right. 1. The Temperature slider controls the heat of the metal filament inside the light. Scientists use the Kelvin scale to measure the temperature of very hot objects. It is like the Celsius scale except 0 K (absolute zero) is the coldest anything can ever be. Slowly move the Temperature slider all the way to the right. What happens? The color of the light changes from red orange to yellow, and the popcorn pops very fast. The light energy emitted by the flashlight is called radiation. 2. Slide the lens so the distance to the flashlight is 40 cm. Press Play ( ). What happens? The popcorn popped very fast, 1.2 seconds. 3. Do you think the kernel will pop if you place cardboard in front of the flashlight? No it will not 4. Click Reset ( What happens? ). At the top of the Gizmo, next to Obstacle, select Cardboard. Press Play. The popcorn is shielded from the radiation and does not pop. Student Exploration: Radiation Question: How does heat get from the flashlight’s metal filament to the kernel? 1. Observe: Press Play. How long does it take the kernel to pop? _____61.3 s__________________ 2. Form hypothesis: Inside the light bulb is a very hot piece of metal, called the filament. It gives off light because it is so hot. In addition, the glass bulb gets hot and heats the air. How do you think heat gets from the filament to the kernel? Heat gets from the filament to the kernel by radiation waves. It travels by heat waves from the radiation. The filament is heated by the electricity moving through the bulb. 3. Predict: Click Reset and select Cardboard. This blocks all light and some of the hot air. Based on your hypothesis, how will this affect popping time? Explain. If the cardboard is an obstacle in front of the kernel, it will absorb the heat waves and will block it from reaching the kernel. 4. Test: Click Play or Fast forward ( ). Was your prediction correct? Yes it was. 5. Predict: Click Reset and select Red glass. This lets most of the light through but still blocks some air. What do you think will happen? Explain. I think it will pop the kernel because the heat waves can travel through the red glass. 6. Test: Click Play or Fast forward. What did you find? My prediction was correct. 7. Draw conclusions: When the popcorn kernel popped, was it because it was heated by light (radiation) or hot air from the flashlight? Explain how you know this. It's the radiation because the light travels from the flashlight to the kernel, so the kernel can be Student Exploration: Radiation popped. And hot air was blocked by lens, but this didn't change popping time.