Change in temperature and length problem help

AI Thread Summary
To determine the temperature at which a glass rod must be heated to match the length of a lead rod heated to 53.4 degrees Celsius, the thermal expansion formula is used: (change in L)/Lo = (alpha)(change in Temperature). The change in length for both rods must be equal, which means setting the equations for the lead and glass rods equal to each other. The coefficients of linear expansion (alpha) for lead and glass are necessary constants for this calculation. To solve for the temperature of the glass, one must rearrange the equation to isolate the temperature variable. Understanding how to equate the changes in length is crucial for solving the problem effectively.
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Lead rod and glass rod have same length at 20.8 degrees celcius. The lead rod is heated to 53.4 degrees celcius. At what temperature must the glass be heated so they are the same length?

I know that (change in L)/Lo = (alpha)(change in Temperature)

but I am not sure how to set (change in L of lead) = (change in L of glass) and i don't know what variables to use to solve for T of glass.

Can anyone help me get started on this one. Much appreciated!
 
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What is alpha for lead and glass? Can you write a thermal expansion equation for the glass rod?
 
they are just some constants...but i don't know how to set these to equations equal to each other to start the problem...
 
Why can't you just set them equal?
 

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