Spot welding of two 1 mm thick sheets of steel (density = 8000 kg/m ) is carried out successfully by passing a certain amount of current for 0.1 second through the electrodes. The resultant weld nugget formed is 5 mm in diameter and 1.5 mm thick. If the latent heat of fusion of steel is 1400 kJ/kg and the effective resistance in the welding operation is 200 -ohms, the current passing through the electrodes is approximately

Spot welding of two 1 mm thick sheets of steel (density = 8000 kg/m )

1.	Spot welding of two 1 mm thick sheets of steel (density = 8000 kg/m ) is carried out successfully by passing a certain amount of current for 0.1 second through the electrodes. The resultant weld nugget formed is 5 mm in diameter and 1.5 mm thick. If the latent heat of fusion of steel is 1400 kJ/kg and the effective resistance in the welding operation is 200 -ohms, the current passing through the electrodes is approximately
A.	1480 A
B.	3300 A
C.	4060 A
D.	9400 A
Answer» D. 9400 A

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