Mechanisms at home
Figure 1: A can opener
Figure 2mechanical advantage, which in turn gives us additional strength, grip and lift.lever. It works well to slice through bread because it has a long handle.lever that helps to break the surface of the soil. You provide the power (effort) with your hands, and your foot is the fulcrum. If you hold the handle with one hand and place your other hand on the shaft of the spade, your second hand is the fulcrum.lever that fits exactly onto a nut so that the nut can be tightened or loosened easily.gears to change the direction of movement. The whisk spins faster than the handle turns. The handle is attached to the driver gear, that has many teeth. Imagine that it has 36 teeth. The follower gears have fewer teeth than the driver gear. Imagine that they each have 12 teeth. For every turn of the driver gear, the follower gears will turn three times. This gives the mechanical advantage.levers. The wind pushes against the blade, acting as the force. They also use gears to drive pumps.gears and levers to make it easy to cut through the lid of a can.
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Figure 6
Select any three of the tools listed here and evaluate them on the following pages:
- can opener
- egg beater
- strap spanner for opening bottles
- vice grip
- wire stripper
- ratchet spanner
- nail scissors
- ladder
- secateurs
- paper punch
- stapler
- tweezers
- hammer
- garden fork
- pliers
- screwdriver
Describe three tools that people sometimes use that are not on the list above.
Name of the tool
Who will use it?
What can you do with the tool; what is its purpose?
How does it give you a mechanical advantage?
What material is it made of?
Why is it made of this material?
What other materials could be used to make this tool?
How much do you think you should pay for it?
What can go wrong when using it? How can it harm you?
What safety precautions should you take when you use this tool?
Name of the tool
Who will use it?
What can you do with the tool; what is its purpose?
How does it give you a mechanical advantage?
What material is it made of?
Why is it made of this material?
What other materials could be used to make this tool?
How much do you think you should pay for it?
What can go wrong when using it?How can it harm you?
What safety precautions should you take when you use this tool?
Name of the tool
Who will use it?
What can you do with the tool; what is its purpose?
How does it give you a mechanical advantage?
What material is it made of?
Why is it made of this material?
What other materials could be used to make this tool?
How much do you think you should pay for it?
What can go wrong when using it? How can it harm you?
What safety precautions should you take when you use this tool?
horizon, the sides of the road seem to meet at a point far away, as in this picture.
The horizon is the line where it seems as if the earth’s surface meets the sky.
vanishing point. Although the road doesn’t actually get any narrower, it looks as if the straight lines meet at the horizon and the road vanishes, because of your perspective.
Figure 7: Vanishing point at the horizonperspective.
Perspective means a view. In Technology, it refers to the drawing technique of representing 3D objects in 2D. This means you can draw objects to look real even though you are drawing on a flat surface.
Figure 8: Drawing of a cube in 3D single vanishing point perspective
Draw one face of the cube. Select a vanishing point.
Draw very feint lines from each corner of the cube face to the vanishing point. These are your construction lines.
Draw horizontal and vertical lines for the back of the cube. The corners should connect with the construction lines.
Draw the shape of the cube, the outline, in darker lines.
Figure 9: Adding wood grain makes things look realistic.
Figure 10: Shading helps to make drawings look more 3D.
Figure 11: Making lines in front and on top darkeralso helps to make a drawing look more 3D.
Figure 12: Single vanishing point drawing of the inside of a classroom
Now evaluate your sketch. Compare it to Figure 12.
- Do you think that your sketch is accurate?
- If you continue the lines, would they meet at a vanishing point?
- If not, what do you think you did wrong? How would you correct the sketch?