Material Science - Thermal Properties

1. Find the wrong statement: Specific heat of a material ______________.
(a) Constant for a material 
(b) Heat capacity per unit mass
(c) Extrinsic property 
(d) Has units as J/kg-K.

2. Heat capacity has units as
(a) J/kg.K 
(b) J/mol.K 
(c) J.ohm/sec.K²
(d) W/m.K

3. Units for thermal conductivity
(a) J/kg.K 
(b) J/mol.K 
(c) J.ohm/sec.K²
(d) W/m.K

4. Lorentz constant has units as
(a) J/kg.K 
(b) J/mol.K 
(c) J.ohm/sec.K²
(d) W/m.K

5. Thermal expansion of a material has units as
(a) J/kg-K 
(b) J/mol-K 
(c) J.ohm/sec.K2 
(d) 1/°C

6. Polymers have thermal conductivities in the range of
(a) < 1 
(b) 1-10 
(c) 10-100 
(d) >100

7. Polymers have thermal expansion coefficients in the range of _____x10-6.
(a) 0.5-15 
(b) 5-25 
(c) 25-50 
(d) 50-400

8. Coefficient of thermal expansion for ceramics is the range of _______x10-6.
(a) 0.5-15 
(b) 5-25 
(c) 25-50 
(d) 50-400

9. Metals have thermal conductivities in the range of
(a) < 1 
(b) 1-5 
(c) 5-25 
(d) 20-400

10. Heat capacity of most materials is approximately equal to ________.
(a) R 
(b) 2R 
(c) 3R 
(d) R/2


Answers

    1. c    2. b    3. d    4. c    5. d
    6. a    7. d    8. a    9. d    10. c

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