6. Kind of Material
• Quantified by a constant value
for coefficient of thermal
expansion for some materials
• The higher the coefficient, the
higher the expansion
• Symbol used - α
7. Original Dimension
• Greater original dimension,
greater the expansion.
• L for linear
• A for area
• V for volume
8. ΔL = α·L0·ΔT
Change in Coefficient of Original
dimension expansion length
Change in
temperature
18. 2. Why is it
advisable to allow
telephone lines to
sag when stringing
them between
pokes in summer?
19. 3. What is the change in length of
a metal rod with an initial length
of 2 meters, a coefficient of
thermal expansion 0.00002 /K and
a temperature change of 20 K?
20. 4. Suppose you have a 0.05 L
container made of glass that is at
283 K. You raised its temperature
to 303 K. By how much will its
volume increase? (glass = 25.5
x10-6 1/K)
21. 5. A steel rail is 24.4m
long. How much does it
expand during a day
when the low
temperature is 291 K
and high temperature is
306 K? (Steel = 12 x10 1/K)
-6
22. 6. The length of a brass bar is 150
cm at 40 C. What will be its length
at 100 C?
(α = 19 x 10-6/K)
23. 7. An aluminum flag pole is
20.0 m tall on a -15 C winter’s
day. How much higher will the
flag fly from the pole on a hot
42 C summer day?
24. 8. What amount of change in
temperature did a 0.25 kg copper
metal undergo when it is initially
5.0 m long and expanded by
0.00002 m?
25. 9. A glass flask whose volume is 1000.0
cm 3 at 0.0 C is completely filled with
mercury at this temperature. When
flask and mercury are warmed to 80.0
C, 12.5 cm3 of mercury overflow.
Compute the coefficient of volume
expansion of the glass.