How is simple machine useful in lifting thing

Simple machines increase force, increase distance, and change direction

Is there a relationship between the distance the load force moves and the distance the effort force moves?

Absolutely! He explains this in the mechanical advantage videos but more easily you can think of it like a wrench turning a stuck bolt. Just using the wrench doesn't work but if you put a pipe on the handle of the wrench to extend the handle, the bolt easily breaks loose. Why? Because the force you apply times the distance of the handle creates what we call a "moment" (a turning force) on the bolt. Mathematically expressed" F * d = P (where P is the moment)

in the middle of the video how did he know to put on the coins

it was probably part of an experiment he had to demonstrate.

What materials do you use for this demonstration so that we can try a hands-on as well? Thanks!

Hi! You could use a ruler and a slim pencil rubber. The advantage of using a ruler is that you can literally measure the distances as you change the mechanism! And the rubber won't let the ruler slide apart, but remeber that it has to be slim, otherwise it won't represent a fulcrum. As for the weight, some coins will do the job. Hope you can do it yourself! Thank you!

in a lever just like the fulcrum was moved to different positions to equalise the position of load and effort... does situation comes where the load has to be moved towards the fulcrum to balance the lever arrangement,, if so can load be moved by keeping fulcrum intact?

yes in the 2nd class lever the load is near the fulcrum eg luggage bag

Main content

Course: High school physics > Unit 5

Lesson 8: Explore simple machines

Lever

Google Classroom

PLEASE NOTE: Some of the videos in this section are silent to allow the viewer to make their own observations about what is happening and respond to the questions posted below.

Khan Academy video wrapper

See video transcript

This video has no sound.

1. What happens to the amount of force needed to move the right side when the fulcrum is shifted to the right?

2. What happens to the distance that left side travels when the fulcrum is shifted to the right?

3. When the fulcrum is shifted to the right, which side has a mechanical advantage and which side has a mechanical disadvantage?

If you are doing high school level math then you may want to check out these mechanical advantage lever videos:

Khan Academy video wrapper

Introduction to mechanical advantageSee video transcript

Khan Academy video wrapper

Mechanical advantage (part 2)See video transcript

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ilagniv
Posted 10 years ago. Direct link to ilagniv's post “How is simple machine use...”
How is simple machine useful in lifting thing
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(9 votes)
Answer
- Yellow Shiƒt»
  Posted 10 years ago. Direct link to Yellow Shiƒt»'s post “Simple machines increase ...”
  Simple machines increase force, increase distance, and change direction
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  (6 votes)
Kasey
Posted 9 years ago. Direct link to Kasey's post “Is there a relationship b...”
Is there a relationship between the distance the load force moves and the distance the effort force moves?
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(6 votes)
Answer
- benjamin.r.miner
  Posted 9 years ago. Direct link to benjamin.r.miner's post “Absolutely! He explains t...”
  Absolutely! He explains this in the mechanical advantage videos but more easily you can think of it like a wrench turning a stuck bolt. Just using the wrench doesn't work but if you put a pipe on the handle of the wrench to extend the handle, the bolt easily breaks loose. Why? Because the force you apply times the distance of the handle creates what we call a "moment" (a turning force) on the bolt. Mathematically expressed" F * d = P (where P is the moment)
  Button navigates to signup page
  (13 votes)
VeronicaZheng2014
Posted 10 years ago. Direct link to VeronicaZheng2014's post “What materials do you use...”
What materials do you use for this demonstration so that we can try a hands-on as well? Thanks!
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(4 votes)
Answer
- Daniel Vargas
  Posted 10 years ago. Direct link to Daniel Vargas's post “Hi! You could use a ruler...”
  Hi! You could use a ruler and a slim pencil rubber. The advantage of using a ruler is that you can literally measure the distances as you change the mechanism! And the rubber won't let the ruler slide apart, but remeber that it has to be slim, otherwise it won't represent a fulcrum. As for the weight, some coins will do the job. Hope you can do it yourself! Thank you!
  Button navigates to signup page
  (8 votes)
Dalton Lee
Posted 10 years ago. Direct link to Dalton Lee's post “How does the machine not ...”
How does the machine not have one side go down at first? At somewhere around
1:20
the lever should be tilted the other way because there is no force being applied on the opposite side.
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(4 votes)
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24crawford.rash
Posted 9 years ago. Direct link to 24crawford.rash's post “in the middle of the vide...”
in the middle of the video how did he know to put on the coins
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(5 votes)
Answer
- Ainsley M
  Posted 8 years ago. Direct link to Ainsley M's post “it was probably part of a...”
  it was probably part of an experiment he had to demonstrate.
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  (4 votes)
Vedanjali
Posted 10 years ago. Direct link to Vedanjali's post “when the weights were add...”
when the weights were added in the 3rd type of lever, why did the left side go downwards even though there was a large number of coins on the other side?
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(6 votes)
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26nevaehstellwag
Posted 4 years ago. Direct link to 26nevaehstellwag's post “Why does weight matter an...”
Why does weight matter and why do we need to know the weight of something?
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(5 votes)
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thejagw1
Posted 8 years ago. Direct link to thejagw1's post “In the lever video , what...”
In the lever video , what would happen if the pivot was in the middle section and a brick was place on top of the middle
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(5 votes)
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Luc Raderman
Posted 3 years ago. Direct link to Luc Raderman's post “Since both sides of the l...”
Since both sides of the lever are trying to move around the fulcrum, is there a centripetal force associated with the fulcrum?
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(5 votes)
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smivas21
Posted 9 years ago. Direct link to smivas21's post “in a lever just like the ...”
in a lever just like the fulcrum was moved to different positions to equalise the position of load and effort... does situation comes where the load has to be moved towards the fulcrum to balance the lever arrangement,, if so can load be moved by keeping fulcrum intact?
Button navigates to signup pageButton navigates to signup page
(4 votes)
Answer
- raj basu
  Posted 7 years ago. Direct link to raj basu's post “yes in the 2nd class leve...”
  yes in the 2nd class lever the load is near the fulcrum eg luggage bag
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  (2 votes)