Question

Pyrex =
9 x10^-6

Aluminum= 25 x10^-6

An aluminum cap which serves as a cover to a glass pyrex jar is tightly attached to the glass; To open the jar, it was exposed to a hot water bath and the temperature was noted at 70 Celsius. The inside diameter of the cap is 6.0 cm at 30 Celsius. Find the difference in radius (cm) that will result by this method

Answer 1

so we know that the cap is from aluminiu and original - initial has a diameter of 6,0 cm at 30 C°
the hot water bath at temp. of 70 C° to open the jar what radius changes will result ?
if i understand it correct

Answer 2

Yes

Answer 3

Pyrex (glass container) =\(9 \times 10^\text{-6}\)

Aluminum (lid) \(25 \times 10^\text{-6}\)

here you go jhonyy, I know that was kind of confusing on what Pyrex was, but nothing to worry about.

Answer 4

ok ty. but now we need get the dilatation of the glass at 70 C° when we know that iniitial has a diameetr of 6 cm at 30 C°
but like an idea if the glass jar will be dilated so i think the aluminium cape will dilate too

Answer 5

do you know how to solve it?

Answer 6

so idk. if the dilatation is proportional with the temperature changes ? if yes so i think than we can use the rule of 3 simple to get the diameter on 70 C°

Answer 7

yes it is

Answer 8

@extrinix your opinon pls. ?

Answer 9

so in this way we can write

6 cm in 30 C°
x cm in 70 C° - cross multiplie and calcule the x value

x = ?

Answer 10

Looks like you are correct on that jhonyy

Answer 11

ohh - tysm

and from this calcule we can make the difference of diameters and so one the difference of radius too

Answer 12

@extrinix but what idk. these details with Pyrex and aluminium where we need using ?

Answer 13

so at \(30°C\) the lid is at 6.0 cm
and using the 2 equations

Pyrex (glass container) =\(9 \times 10^\text{-6}\)

Aluminum (lid) \(25 \times 10^\text{-6}\)

it wants you to find the difference from when it was \(30°C\) to after it was put in a hot water bath, \(70°C\), in radius/cm

Answer 14

so this mean that you need calcule these changes for every two material - glass container and aluminium in case of 70 C°
yes ?

Answer 15

yes.