CWB level 3 module 20 Questions with 100% Correct Answers

CWB level 3 module 20 Questions with 100%
Correct Answers
Compared to non metals, metals have Correct Answer:
1. High electrical conductivity


2. High thermal conductivity


3. High specific gravity


4. often ductile and can be formed


5. metal's physical properties can be greatly influenced
by it's alloying materials.


In metals, electrical and thermal conductivity .. Correct
Answer: Paralell each other


Cu and Al are used as .. Correct Answer: electrical
conductors


Gold and silver are used as .. Correct Answer: electrical
contacts


Electrical conductivity helps for .. Correct Answer: arc
welding and resistance welding

, Very high thermal conductivity makes .. Correct Answer:
arc welding difficult and resistance welding impossible
bcz heat is rapidly removed from weld


Thermal conductivity of Cu Correct Answer: 394 W(m c)
/ 230 BTU


Electrical resistivity of Cu Correct Answer: 1.72 x 10 ^ -8
ohm m


Thermal conductivity of Aluminum Correct Answer: 222
W(m c) /130 BTU


Electrical resistivity of Al Correct Answer: 2.83 x 10 ^ -8
ohm m


Thermal conductivity of Carbon steel Correct Answer: 46
W(m c) /26.8 BTU


Electrical resistivity of Carbon steel Correct Answer: 16.0
x 10 ^ -8 ohm m


Pure Cu Correct Answer: Cannot be seam / spot/
projection welded