Will it roll, or not? What stops things from rolling?

Things roll faster down a steeper ramp...but WHY?

In this activity, students see these concepts for themselves through playing with ramps and a variety of 'rollers' and surfaces.

Round things will roll, square-ish things will not roll. We use wheels to help move things that aren't round. Things roll and slide more slowly on a sticky or bumpy surface. The surface has more friction.

The activity is separated into three different parts that can be staggered throughout the day or week.

Round the Circle: printable guide.

This activity was developed and tested with preschool and kindergarten educators as part of Science World's Big Science For Little Hands program.

### Objectives

• Understand that a ramp is a slanted surface with one end higher than the other.

• Predict and observe how differently-shaped objects will move on a ramp (e.g. slide, roll, or not move at all).

• Experiment with different surfaces and steepness.

### Materials

• Per Group:
a ramp (use a big piece of cardboard, a storage box lid, or a piece of wood; prop up one end with blocks or cushions)
a variety of small balls and cylinders (objects that will roll)
square, rectangular and/or triangular blocks
empty (or full!) plastic bottles

Part 2:
the above, plus towels, rugs, or pieces of non-slip carpet underlay (1 per group)

Part 3:
a ramp
toy cars/trucks

### Key Questions

• Part 1: Can you make each object move from the top of the ramp to the bottom? Which shapes roll and which shapes slide? Are there any shapes that don't move at all?
• Part 2: Do the objects move the same way down the ramp when you cover it with your towel/rug/carpet underlay? Why or why not?Part 3: Do some cars or trucks move faster than the others? Why or why not? Are some heavier than others?How did you change your ramp to make them go faster?

### What To Do

Part 1: Different Shapes

1. Build your ramp. Prop your surface up on a stack of blocks or cushions.
2. Place objects on the ramp and see how they move down it.

Part 2: Friction

1. Cover your ramp with a towel, a rug, or a piece of non-slip carpet underlay.
2. Place the same objects from Part 1 on the ramp. Now how do they move?

Part 3: Races/Steepness

1. Choose a car or truck to race down the ramp.
2. Race a friend’s car. Which one goes faster?
3. Change your ramp to make both cars go faster, then race again.

### Extensions

• Try a friction race. Cover one half of a ramp with a bumpy surface and leave the other half bare. Race two objects, one on each side, and see which side 'wins' - the smooth or bumpy side.
• Try a really big ramp - use the slide at a playground or an accessabilty ramp at a building!
• If possible, invite a construction worker or engineer to visit your class and discuss how they use ramps in their work.
• Keep the fun 'on a roll' and go bowling! If visiting a bowling alley is not an option for you, many stores sell children's bowling sets, or you can get creative and make your own set using everyday items. The UCreate blog offers a simple tutorial for making a plastic bottle bowling set.

### Other Resources

UCreate | Plastic Bottle Bowling Tutorial

Survivors

Artist: Jeff Kulak

Jeff is a senior graphic designer at Science World. His illustration work has been published in the Walrus, The National Post, Reader’s Digest and Chickadee Magazine. He loves to make music, ride bikes, and spend time in the forest.

Egg BB

Artist: Jeff Kulak

Jeff is a senior graphic designer at Science World. His illustration work has been published in the Walrus, The National Post, Reader’s Digest and Chickadee Magazine. He loves to make music, ride bikes, and spend time in the forest.

Comet Crisp

Artist: Jeff Kulak

Jeff is a senior graphic designer at Science World. His illustration work has been published in the Walrus, The National Post, Reader’s Digest and Chickadee Magazine. He loves to make music, ride bikes, and spend time in the forest.

T-Rex and Baby

Artist: Michelle Yong

Michelle is a designer with a focus on creating joyful digital experiences! She enjoys exploring the potential forms that an idea can express itself in and helping then take shape.

Buddy the T-Rex

Artist: Michelle Yong

Michelle is a designer with a focus on creating joyful digital experiences! She enjoys exploring the potential forms that an idea can express itself in and helping then take shape.

Geodessy

Artist: Michelle Yong

Michelle is a designer with a focus on creating joyful digital experiences! She enjoys exploring the potential forms that an idea can express itself in and helping then take shape.

Science Buddies

Artist: Ty Dale

From Canada, Ty was born in Vancouver, British Columbia in 1993. From his chaotic workspace he draws in several different illustrative styles with thick outlines, bold colours and quirky-child like drawings. Ty distils the world around him into its basic geometry, prompting us to look at the mundane in a different way.

Western Dinosaur

Artist: Ty Dale

From Canada, Ty was born in Vancouver, British Columbia in 1993. From his chaotic workspace he draws in several different illustrative styles with thick outlines, bold colours and quirky-child like drawings. Ty distils the world around him into its basic geometry, prompting us to look at the mundane in a different way.