ASSIGNMENT DUE BY 24 HRS

1. A concave mirror has a centre of curvature of 20 cm. A 1.5 cm candle is placed 5 cm in front of the mirror.

1. Draw a scale diagram showing how an image is formed. Be sure to label, and include all points and measurements for full marks.

2. Use the mirror formula to determine the exact location, orientation, and size of the image.

2. Repeat the above question for an object placed 15 cm in front of the mirror.

3. Challenge: Mathematically calculate the location of the object that results in a magnification of - 1.5x for the mirror used in question 1 and 2.

In this lab activity, you will create convex and concave jello lenses and observe how light rays bend as the move through the medium.

· 3 packets of jello (preferably light colours and sugar-free)

· hot water (according to package directions)

· baking pan

· strong flashlight

· shoe box

Performing hands-on lab activities is another way to learn and discover how science concepts apply to our everyday lives. However, it can also be dangerous if you do not take steps to perform these activities safely. We have made every effort to ensure that these activities are safe to perform in the presence of an adult (e.g. a teacher or parent). It is important for you to use good judgement and exercise every precaution in order to avoid accidents that may result in injury.

If you have any questions about the materials or procedure of a lab activity, you are to contact either your teacher or the Science Department , prior to beginning any lab activity.

1. Mix the packets of jello with the hot water according to the package directions. Do not add the cold water.

2. Stir to dissolve powder.

3. Refrigerate overnight.

4. Remove jello from the pan onto a cutting board surface.

5. Cut the jello into shapes that resemble convex and concave lenses. Make a variety of different curvatures.

1. Cut a narrow slit (width: 1 mm; length: 5 cm) at one end of the shoe box.

2. Fix a strong flashlight up against the slit so that it can be easily turned on and off.

1. Perform this activity in a dark room. Turn on the flashlight.

2. Direct the ray of light through the jello lenses and observe how the light bends as it moves through and exits the medium.

3. Direct the ray of light through the jello lenses at different angles and observe.

1. What did you observe when the light rays moved through a convex lens?

2. Why do you think this happened?

3. What did you observe when the light rays moved through a concave lens?

4. Why do you think this happened?

5. What similarities/ differences did you notice when doing this activity using lenses of different curvatures?

1. Referring to the ray diagram for the convex lenses, draw an accurate scale ray diagram for a lens that has a focal length of 8 cm. A candle of height 1 cm is placed exactly 16 cm in front of the lens.

2. Now use the lens formula to calculate the exact location and size of the image for the setup described in #1.

Complete the ray diagram showing how a young lady can see herself from head to toe when standing in front of a vertical mirror.

Does she need a mirror that is as tall as she is? Explain.