In this picture, the blue circle is a wheel, and
the line sticking out of it is a bar attached to the wheel.
The bar has a length of 10.
the line sticking out of it is a bar attached to the wheel.
The bar has a length of 10.
When you push something, you apply force to it.
If you push on the bar, the wheel will turn.
You can find its torque by multiplying the force that you use push on it by the distance you’re standing from the center of the wheel.
If you push on the bar, the wheel will turn.
You can find its torque by multiplying the force that you use push on it by the distance you’re standing from the center of the wheel.
10 ft x 2lbs=20ft lbs
Therefore, the torque would be 20 foot-pounds.
Foot-pound is a common way of measuring torque.
(One foot-pound is the force of something that is pushing with
one pound of pressure one foot from the center of the circle.)
Therefore, the torque would be 20 foot-pounds.
Foot-pound is a common way of measuring torque.
(One foot-pound is the force of something that is pushing with
one pound of pressure one foot from the center of the circle.)
So, hopefully you understand that, but what if the bar is at an angle and you still push straight up?
Well, even if you’re pushing on the very end of the bar, the same place that you were pushing on when the bar was horizontal (straight side-to-side),
you’ll need to move closer to the center of the wheel, so you’ll have less leverage.
(the distance is measured perpendicular--straight sideways, like two sides of a square--from the center of the wheel.)
To understand this, think of reaching for something that’s at the same height above the ground as your arm.
Imagine that you can just barely reach it.
If you kneel down in the same spot and try to reach for it again, your arm will not be long enough to reach it.
So, now that you understand that, think about pushing a bar that starts at an angle.
If you want to be able to reach the bar, you’ll have to stand underneath it, which makes you stand closer to the center of the wheel.
Well, even if you’re pushing on the very end of the bar, the same place that you were pushing on when the bar was horizontal (straight side-to-side),
you’ll need to move closer to the center of the wheel, so you’ll have less leverage.
(the distance is measured perpendicular--straight sideways, like two sides of a square--from the center of the wheel.)
To understand this, think of reaching for something that’s at the same height above the ground as your arm.
Imagine that you can just barely reach it.
If you kneel down in the same spot and try to reach for it again, your arm will not be long enough to reach it.
So, now that you understand that, think about pushing a bar that starts at an angle.
If you want to be able to reach the bar, you’ll have to stand underneath it, which makes you stand closer to the center of the wheel.
8 feet x 2 lbs=16 foot-pounds
Even if the bar is 10 feet long, it you are
only standing 8 feet from the center of the wheel
(like in the picture) and applying 2lbs of force to the bar,
you will be pushing the wheel with a force of 16 foot-pounds.
If you think about it, after you’ve pushed a horizontal bar up or down, it isn’t horizontal anymore, and your leverage will decrease.
Even if the bar is 10 feet long, it you are
only standing 8 feet from the center of the wheel
(like in the picture) and applying 2lbs of force to the bar,
you will be pushing the wheel with a force of 16 foot-pounds.
If you think about it, after you’ve pushed a horizontal bar up or down, it isn’t horizontal anymore, and your leverage will decrease.
This means that you’ll have the most leverage right when the bar is horizontal
and the least leverage when the bar is vertical (sticking straight up).
This is because the distance you are from the center of the wheel is 0 feet.
(At this point, you would probably step to one side and push the bar over.
If you stood right underneath it, you wouldn’t be able to push it sideways.)
and the least leverage when the bar is vertical (sticking straight up).
This is because the distance you are from the center of the wheel is 0 feet.
(At this point, you would probably step to one side and push the bar over.
If you stood right underneath it, you wouldn’t be able to push it sideways.)
Now, imagine that we’ve taken away the 10-foot bar, and we now have a 12-foot bar.
This works in the same way as the 10-foot bar, only now we use
the distance of 12 rather than 10 when the bar is horizontal.
This works in the same way as the 10-foot bar, only now we use
the distance of 12 rather than 10 when the bar is horizontal.
12 feet x 2 lbs=24 foot-pounds
Once again, when the bar is tilted, just measure sideways from the center to find the distance.
Once again, when the bar is tilted, just measure sideways from the center to find the distance.