Teeter Totter Balance: Why Does the Lighter Person's End Go Down?

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    Word problem
In summary, two people, one heavy and one light, are balanced on a teeter totter. When they both move closer to the fulcrum, the seesaw will tilt downwards on the lighter person's end. This is because the amount of force exerted on each side depends on the distance from the fulcrum, as shown by the equation m1*d1 = m2*d2. The side with the greater force will go down while the other side goes up, and the numbers in the equation represent the force being exerted.
  • #1
physicsgurl12
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Homework Statement



suppose that a heavy person and a light person are balanced on a teeter totter made of plank wood. each person moves toward the fulcrum 25cm. why will the lighter persons end go down??

Homework Equations




not needed

The Attempt at a Solution


something about forces and gravity??
 
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  • #2
Do you know the math to write the balancing equation for the two sides of the seesaw?
 
  • #3
phinds said:
Do you know the math to write the balancing equation for the two sides of the seesaw?

math? i don't think so.
 
  • #4
OK, I'm a bit puzzled as to how you can be working on such a simple problem and not know the math. What grade are you in?
 
  • #5
phinds said:
OK, I'm a bit puzzled as to how you can be working on such a simple problem and not know the math. What grade are you in?

im a senior. i don't understand why we need math. were not finding a number.
 
  • #6
physicsgurl12 said:
im a senior. i don't understand why we need math. were not finding a number.

No, you're not trying to get a number, you're trying to get an ANSWER, and the quantitative asnwer is a number and if you don't understand how to get the quantitative answer, you don't understand the answer.

Do you have no idea how a fulcrum works mathematically?
 
  • #7
um not really. its like the piviot point. that's about all i know
 
  • #8
If you had a seesaw with a 100 pound kid sitting out 10 feet from the center (the fulcrum), how much effort do you think it would be to keep him in the air if you could put your hand on the (strong, but weightless) seesaw a mile out on the other end?

How about 100 feet out?

How about 1 foot out?

What does thinking about this tell you?
 
  • #9
that the amount of force depends on the distance
 
  • #10
good. Can you quantify that?
 
  • #11
umm i can try.
m1*d1=m2*d2
 
  • #12
excellent.

SO ... if we have, for example, a 100lb kid 10 feet out and a 200 lb man 5 feet out, then they balance, according to your equation (which is correct).

Now do the math if they both move in 1 foot.
 
  • #13
900 =600
 
  • #14
well, actually they are NOT equal, are they? So what does it mean in terms of who goes up and who goes down?

What do those numbers represent?

[by the way, check your math]
 
  • #15
sorry 800 haha. those number represent the force? It means the fat kid would go down?
 
  • #16
physicsgurl12 said:
sorry 800 haha. those number represent the force? It means the fat kid would go down?

Yes it represents force. Which side is exerting the most force? Does the most force cause the side that has it to go up or does the OTHER side go up?
 

What is a Teetertotter word problem?

A Teetertotter word problem is a type of math problem that involves a balance scale, or teeter-totter, and requires the solver to find the missing value in order to balance the scale. The missing value is usually represented by a variable.

What is the formula for solving a Teetertotter word problem?

The formula for solving a Teetertotter word problem is: weight on one side * distance from fulcrum = weight on the other side * distance from fulcrum. This is also known as the law of the lever.

What are the key words to look for in a Teetertotter word problem?

Some key words to look for in a Teetertotter word problem include "balance", "equal", "even", "same", "equilibrium", "ratio", and "proportion". These words may indicate that the problem can be solved using the Teetertotter formula.

What strategies can I use to solve a Teetertotter word problem?

One strategy for solving a Teetertotter word problem is to set up a table or diagram to represent the weight and distance values on each side of the scale. Another strategy is to use trial and error, plugging in different values for the missing variable until the scale is balanced.

What are some real-life applications of Teetertotter word problems?

Teetertotter word problems can be found in various fields such as physics, engineering, and even everyday situations like grocery shopping. For example, a physics problem may involve finding the weight of an object on one side of a pulley system in order to achieve equilibrium. In grocery shopping, you may use the concept of balance to figure out how many pounds of fruits or vegetables you can buy for a certain amount of money.

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