# Physics AS SI Units Help

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#1
Could someone tell me the answer to this question so I can double check my own since Google won't tell me?

Show that the following equation is homogeneous using units.

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3 weeks ago
#2
(Original post by LLT05)
Could someone tell me the answer to this question so I can double check my own since Google won't tell me?
No. Over here, people only help, not provide solutions.
(Original post by LLT05)
Show that the following equation is homogeneous using units.

What have you done so far?
hint: look at the words in bold.
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#3
(Original post by 0ptics)
No. Over here, people only help, not provide solutions.

What have you done so far?
hint: look at the words in bold.
LHS: Force = m kg/s^2
RHS: mass = kg, speed = m/s^2, radius = ?

I think my answer is just kg m/s^2, making the equation homogeneous. But I'm confused about what I'm supposed to do with the radius?
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3 weeks ago
#4
(Original post by LLT05)
LHS: Force = m kg/s^2
RHS: mass = kg, speed = m/s^2, radius = ?

I think my answer is just kg m/s^2, making the equation homogeneous. But I'm confused about what I'm supposed to do with the radius?
Do you know the units for radius? Radius is a length. Btw, you might want to recheck your units for speed.
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#5
(Original post by 0ptics)
Do you know the units for radius? Radius is a length. Btw, you might want to recheck your units for speed.
Is speed just m/s? I thought it would be squared since in the equation speed is squared
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#6
(Original post by 0ptics)
Do you know the units for radius? Radius is a length. Btw, you might want to recheck your units for speed.
Is the equation even homogeneous?
1
3 weeks ago
#7
(Original post by LLT05)
Is speed just m/s? I thought it would be squared since in the equation speed is squared
No and yes. Speed is squared, so the units are also squared. You wrote m/s^2, which is incorrect as you’ve only squared the s, not the m.
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3 weeks ago
#8
(Original post by LLT05)
Is the equation even homogeneous?
It is. Why do you think otherwise?
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#9
(Original post by 0ptics)
It is. Why do you think otherwise?
I was wondering how the equation could be homogeneous if force = m kg/s^2 and I have kg (mass) and m/s^2 (speed) then I thought that I have all I need for the equation so what is radius or why do I have to square the m as well. I think I get it now. Thanks
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3 weeks ago
#10
(Original post by LLT05)
I was wondering how the equation could be homogeneous if force = m kg/s^2 and I have kg (mass) and m/s^2 (speed) then I thought that I have all I need for the equation so what is radius or why do I have to square the m as well. I think I get it now. Thanks
So I presume that you now know why you have to square the m in speed as well as knowing the units for radius. One more thing. The units for force is kg m/s^2, not m kg/s^2, big difference!
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#11
(Original post by 0ptics)
So I presume that you now know why you have to square the m in speed as well as knowing the units for radius. One more thing. The units for force is kg m/s^2, not m kg/s^2, big difference!
Why is there a big difference? My teacher wrote it down that way so I thoight it was correct.

Also if I had s = m / m/s^2, would the m cancel out leaving me with s = s^2, and would that equation be homogenous.
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