Do Now: Look at the tape on the communicator on your desk and - - PowerPoint PPT Presentation

Do Now:

Look at the tape on the communicator on your desk and choose which one would be best for the following:

1. Which one would be best for wrapping a present with nice wrapping paper? Why? 2. Which one would be best for putting on your bike when riding at night? Why? 3. Which one would be best for protecting your windowsill when painting the house? Why?

3 types of objects that light waves interact with

• 1. Reflective: an object that the light reflects, or bounces off of.
• 2. Transparent: an object that light can travel through without

bending or breaking.

• 3. Opaque: can’t be seen through, or non-transparent.

How do shadows form?

Shadows are produced when light hits an opaque object which prevents the light beams from passing through. When an object blocks the light’s path, then darkness appears on the other side. This darkness is called a shadow. The sun is a source of light that when hits an object causes shadows. As the earth rotates each day, the sun appears to change position in the sky and changing angles of sunlight affect the appearance of shadows. For instance, on a sunny day, you can stand a stick in the ground and watch its shadow move and change shape. When the sun gets low in the sky, the stick’s shadow gets longer.

How can we change the size of a shadow?

Each team is going to work on putting on a shadow puppet show. In your puppet show, you have a tree that is growing over time. However, you only have 1 cutout of a

• tree. As a team, figure out how to change the size of a shadow to figure out how to

show your tree is changing size over time.

Exit Ticket Explain what causes shadows and how to change the size of them in your own words.