# Conservation of Energy

Main Image
Activity Language
Time Needed for Activity
Subjects

Students learn about conservation of energy, measure the bounce of a ball at different heights and then use elastic potential energy to make a paper glider fly having kinetic energy.

This is an adaptation of an old national office activity on conservation of energy and the foam gliders. Students make a number line and use it to measure the bounce of a ball at different heights. It has been adapted to be the height of their desk so they can work at their desk and think about where energy went - e.g., some of the energy was transformed to heat, etc. They then use elastic potential energy to make a paper glider fly having kinetic energy.

## What You Need

### Activity 1: Ball Experiment

• 8 balls (1 per group)
• 8 sheets of paper that have been cut lengthwise into 1/3 width of a 8.5 x 11 piece of paper per group
• Tape
• 8 rulers (1 per group)
• Pencils

### Activity 2: Planes

• Card stock triangles
• Paper clips
• Elastics/rubber bands
• Paper straws
• Scissors
• Tape
• Ribbons and stickers
• Safety goggles

Lesson Plan:

### Safety Notes

As a Let’s Talk Science volunteer, safety must be foremost in our minds during all activities. As STEM role models, volunteers must always also model safe science practices.

Always keep in mind the following precautions:

• Emphasize and demonstrate appropriate safety procedures throughout the presentation.
• Be professional but have fun.
• Keep workspaces clean to avoid tripping hazards.
• Allergens should have been checked before reserving the kit (e.g. allergies to latex).

## What To Do

### Activity 1: Ball Experiment

Get the educator to put students into groups and hand out the materials and instructions to the group. Walk around the class and help the students walk through the following experiment:

1. Using a tape measure (or a metre stick), mark along the length of your papers at 10 cm intervals (label the marks from 10 cm – 150 cm)
2. Attach all the pieces of paper to the wall with one short side at floor level (and so on with the short sides attaching to the next piece)
3. Hold your ball at 50 cm (or 0.5 meters). If you drop the ball from this height, how high do you think it will bounce?
4. Drop the ball and check to see how high it bounced
5. Design a chart to record the drop heights and bounce heights of: 50 cm, 100 cm, and 150 cm
• (1) ball dropper – to carefully drop the ball without using any force, from exactly the height recorded
• (1 – 2) watchers – to watch the height of the bounce
• (1) recorder – to write the information on your chart (Note: if there is time the groups may repeat the experiment, exchanging tasks, or using different types of balls)
7. Complete the experiment by dropping the ball from the various heights and recording your results

### Activity 2: Planes

Get the educator to hand out the materials.

Instruct the students through the following steps:

1. Fold back the top 3 cm of the straw and insert the rubber band into the fold
2. Fold the straw over the rubber band and secure the end with tape (this creates the launcher for the plane)
3. Put the paperclip on 1 corner of the paper triangle (this corner will be the one that aligns with the launcher – where the elastic is)
4. Have them tape the triangle to the launcher, leaving a little of the straw sticking out. (Note: you can find an example of this in the kit)
5. Hook the rubber band around the tip of your thumb or finger and pull back on the opposite end of the glider/plane
6. Release the straw and the plane will fly forward (be careful of your thumb as it launches)

For this activity you should designate a launch starting line and ask that the students not cross the line when launches are happening.