1. . Electric heating is better than other sources of heating because of:
(A) All of these
(B) Noise less heating
(C) Non-conducting materials
(D) Pollution free
2. . Which mode of heat transfer is clear example of sun:
(A) Conduction
(B) Radiation
(C) Convection
(D) Induction
3. . In this method, current passes through high resistive element and heat is produced due to (I²R) power losses:
(A) Induction heating
(B) Infrared heating
(C) Resistance heating
(D) Both a and a
4. . Heating pump is a machine that can pump heat from:
(A) Inside to the outside
(B) Both a & b
(C) Outside to inside
(D) None of these
5. . In this method, the material to be heated is taken as a resistance and current passes through it:
(A) Indirect resistance heating
(B) Induction heating
(C) Direct resistance heating
(D) a & d
6. . This furnace is used for production and refining of various grades of steel:
(A) Direct resistance furnace
(B) Induction furnace
(C) Direct Arc furnace
(D) Indirect Arc furnace
7. . Indirect Arc furnace transfers heat to the charge by:
(A) Induction
(B) All above
(C) Conduction
(D) Radiation
8. . In induction heating, amount of heat can be controlled by:
(A) Supply frequency
(B) Flux density
(C) Both A & B
(D) DC voltage
9. . It is suitable heating method for non-conducting materials:
(A) Arc heating
(B) Resistance heating
(C) Dielectric heating
(D) Eddy current heating
10. . Infrared heating is used for:
(A) Paint stoving
(B) Drying of wood furniture
(C) Preheating of plastics prior to molding
(D) All of above
11. . For spot welding, voltage between electrode should be less than:
(A) 3V
(B) 50V
(C) 220V
(D) 400V
12. . This type of welding is frequently used in the automobile and aircraft industries:
(A) Resistance welding
(B) Spot welding
(C) Arc welding
(D) Seam welding