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Physics AS SI Units Help

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.

Force = mass x (speed)^2/radius
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.

Force = mass x (speed)^2/radius

What have you done so far?
hint: look at the words in bold.
Reply 2
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?
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.
Reply 4
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
Reply 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 the equation even homogeneous?
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.
Original post by LLT05
Is the equation even homogeneous?

It is. Why do you think otherwise?
Reply 8
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
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!
Reply 10
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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