Chapter 12

Problem 22

 

A steel ruler is calibrated to read true at 20.0oC.  A draftsman uses the ruler at 40.0oC to draw a line on a 40.0oC copper plate.  As indicated on the warm ruler, the length of the line is 0.50m.  To what temperature should the plate be cooled, such that the length of the line truly becomes 0.50m?













Chapter 12

Problem 33

 

At the bottom of an old mercury-in-glass thermometer is a 45mm3 reservoir filled with mercury.  When the thermometer was placed under your tongue, the warmed mercury would expand into a very narrow cylindrical channel, called a capillary, whose radius was 1.7 x 10-2 mm.  Marks were placed along the capillary of the glass that indicated the temperature.  Ignore the thermal expansion of the glass and determine how far (in mm) the mercury would expand into the capillary when the temperature changed by 1.0 Co.