How do wheels make life easier?
Reduced friction: Wheels reduce friction between an object and the ground so that objects can be moved around more easily. If you’ve got a boulder to transport across your backyard, putting it in a wheelbarrow is a lot easier than pushing or dragging it across the lawn.
Magnify a force: It takes less effort to turn a central axle by pushing along an attached wheel’s edge. Larger steering wheels and dials are easier to turn than smaller ones.
Magnify a movement: If you put effort into turning a central axle, you gain lots of movement as the edge of the attached wheel moves through a greater distance.
You can experiment with magnifying force and movement at the Factory’s Weights and Wheels exhibit.
Everyday uses of wheels
Wheels are great for moving cars and bikes along, and they’re handy for other things too:
- water wheels are used to generate electricity as the force of the large wheel is magnified at the axle, allowing the water wheel to drive machinery
- the blades of wind turbines act as spokes of a large wheel, where the force of the blades is magnified at the rotor. This makes a generator spin and produce electric current
- when you turn a screwdriver, you are magnifying the force of the turning handle at the screwdriver’s shaft
- a propellor pushes boats along as the spinning movement at the axle is magnified at the propellor’s blades
- ball bearings are spherical wheels that reduce friction. When you write with a ball-point pen, the power of wheels allows your pen (and ink) to glide across the page.
