Simple Machines B/Compound Machines C

[Unome]

You sure?
The first problem is this

divcanswer.png

Try the second question.

Wait... shouldn't be 10N?

[plaid suit guy2]

You sure?
The first problem is this

divcanswer.png

Try the second question.

Wait... shouldn't be 10N?

...yes

[Unome]

You sure?
The first problem is this

divcanswer.png

Try the second question.

Wait... shouldn't be 10N?

...yes

So ?

[plaid suit guy2]

It't just ends up as 27.84N (exactly as written on the piece of paper I wrote the solution on last night at like 10:30. Tired me is better as physics, as it turns out )

done correctly

[Unome]

It't just ends up as 27.84N (exactly as written on the piece of paper I wrote the solution on last night at like 10:30. Tired me is better as physics, as it turns out )

done correctly

divcanswer.png

Ohh... I just made a math error, subsequently fixed it to figure out how to solve the problem, then remade the same error while actually calculating the answer...

[plaid suit guy2]

I did too, so it's all good. Oh, also,

You sure?
The first problem is this

divcanswer.png

Try the second question.

Now I get it. I forgot the part...

Assuming the lever has a constant density (Click to Show Hidden Text)

4 kg

except... shouldn't the weight of the lever arm increase as the arm goes further away from the fulcrum?

This is an incorrect answer. The weight doesn't increase with the distance, the torques do, but there is a mathematical shorthand: you can assume all of the mass is at the center of mass of the beam, its halfway point.

[UTF-8 U+6211 U+662F]

I did too, so it's all good. Oh, also,

You sure?
The first problem is this

divcanswer.png

Try the second question.

Now I get it. I forgot the part...

Assuming the lever has a constant density (Click to Show Hidden Text)

4 kg

except... shouldn't the weight of the lever arm increase as the arm goes further away from the fulcrum?

This is an incorrect answer. The weight doesn't increase with the distance, the torques do, but there is a mathematical shorthand: you can assume all of the mass is at the center of mass of the beam, its halfway point.

Yeah, I meant the torque.
I tried doing that, but the lever arm itself ended up having more torque then both the other arm and the weight together, so...

[plaid suit guy2]

I did too, so it's all good. Oh, also,

Now I get it. I forgot the part...

Assuming the lever has a constant density (Click to Show Hidden Text)

4 kg

except... shouldn't the weight of the lever arm increase as the arm goes further away from the fulcrum?

This is an incorrect answer. The weight doesn't increase with the distance, the torques do, but there is a mathematical shorthand: you can assume all of the mass is at the center of mass of the beam, its halfway point.

Yeah, I meant the torque.
I tried doing that, but the lever arm itself ended up having more torque then both the other arm and the weight together, so...

yes, it does

[UTF-8 U+6211 U+662F]

This is an incorrect answer. The weight doesn't increase with the distance, the torques do, but there is a mathematical shorthand: you can assume all of the mass is at the center of mass of the beam, its halfway point.

Yeah, I meant the torque.
I tried doing that, but the lever arm itself ended up having more torque then both the other arm and the weight together, so...

yes, it does

Then the load has to have negative weight...
I just figured you did something wrong, so I just did the question wrong...

[Unome]

Answer (Click to Show Hidden Text)

[math](10 m)(20/25*20 kg) + (15 m)(x kg) = (5 m)(15 kg) + (2.5 m)(4 kg)[/math]
[math]x=5kg[/math]
Definitely negative