As you watch the video about inclined planes think about how the man moves the box.
- How do you use incline planes to move objects?
This man is doing some heavy lifting, but this box is too heavy for him. Is there an easier way to get the box into the truck?
He could use a board to slide the box up. When the board is used this way, it is called an inclined plane.
An inclined plane is a flat surface with one end higher than the other. Inclined planes make it possible to move something from a lower place to a higher place with less effort.
You can see inclined planes in many places. This road is an inclined plane that helps the truck get to the top of the hill.
A slide is an inclined plane. If this student jumped from the top of the slide, he would fall straight down with a lot of force and might hurt himself. But if he goes down the slide, he reaches the ground by moving more slowly over a greater distance, and he lands with much less force.
Here is a wooden block and two ramps, or inclined planes, that go up to the same height. One inclined plane is longer than the other. Do you think it will take less force to pull the block up the shorter inclined plane or the longer one? This student uses a rubber band to find out.
I hooked the rubber band to one side of the block. Then I pulled the block up the shorter ramp. The rubber band stretched a long way.
Then I took the block and pulled it up the longer ramp. I had to pull it further, but it was easier to pull, and the rubber band didn't stretch as far.
How far the rubber band stretches is one way of telling how much force it takes to move the block up each inclined plane. If the student lifts the block straight up without the help of any inclined plane, the rubber band will stretch the most of all.
Inclined planes
What do inclined planes allow you to do?
