inclined plane

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Inclined plane: A sloping surface, such as a ramp. An inclined plane can be used to alter the effort and distance involved in doing work, such as lifting loads. The trade-off is that an object must be moved a longer distance than if it was lifted straight up, but less force is needed.

  • Examples: Staircase, Ramp, Bottom of a Bath Tub

One of the fundamental simple machines is the Inclined Plane (animation). There are plenty of examples of uses of the inclined plane throughout history – building the pyramids, loading a ship floating next to a dock, screws for fastening pieces of wood, door stops

Explore – What’s the problem? Why?
Look for places around you where Inclined Planes would solve a problem or make life easier for someone.

Examples – What can it do? * solutions

Engineering – How did they do that? How does it work?
Ask questions and find information to come up with your solution. Questions correspond to the steps in the Engineering Design Process.

  • Ask (What? Ask questions, understand the need, identify the problem, define)

Use an inclined plane to overcome a large resistance by applying a relatively small force through a longer distance than the load is to be raised. Where would using an Inclined plane be a good solution? How would it help to move heavy loads?

  • Imagine (So what? Imagine, brainstorm, explore, discover)

What other options could be considered? Often, the best solution is a bit more complicated. The inclined plane could curve or be made up of several shorter connecting inclined planes.

  • Plan (Now what? Plan, design)

How important is the angle of the inclined plane? How will the angle (or grade) impact the design? The slope, length and height are the key pieces of information for the incline plane design. Depending on who or what will be using the inclined plane and where, there may be limits or restrictions. The ramps used by ancient Egyptians building the pyramids, likely took the form of an inclined plane at the beginning of work, but later stages may have been a straight, gently sloping, linear ramp, or a steep staircase ramp, or a ramp that spiraled up the four sides of the pyramid. No one knows.

Inclined plane
  • Create (Do it. Create, try it out)
    It is easy to make a simple inclined plane with a board or a flat object, and something to hold up one end. Ramps and sloping roads can be simple as well.
    Q: Are there any difficulties constructing the inclined plane?
  • Improve (If this then what? Improve, make it better)
    Q: Where could an inclined plane be used that would be an improvement over something currently in use?

That’s engineering
In classical mechanics, momentum is defined as the product of mass and velocity. It is thus a vector quantity.

  • In the SI system of units, mass is measured in kilograms (kg). Many other units of mass are also employed, such as: grams (g), metric tons, pounds, ounces, long and short tons, quintals, slugs, atomic mass units, Planck masses, solar masses
  • Velocity is a measurement of the rate and direction of motion. The scalar absolute value (magnitude) of velocity is speed. Velocity can also be defined as rate of change of displacement or just as the rate of displacement. It is a vector quantity with dimension length/time. In SI units this is metre per second

Engineering ideas

  • simple machines, complex machines, grade, rise, force, momentum, effort distance, resistance distance, length, height

Do it
Here are some challenges for you to work on…

  • The Ramp – Explore forces, energy and work as you push household objects up and down a ramp. Lower and raise the ramp to see how the angle of inclination affects the parallel forces acting on the file cabinet. Graphs show forces, energy and work.
  • build an incline plane and demonstrate how changing the angle changes the effectiveness of this simple machine

Learn more…