Question:
In a direct current arc welding, the voltage \( V \) (in volt) is related to the arc length \( l \) (in cm) as
\[
V = 30 + 30l.
\]
The open circuit voltage is 80 volts. The maximum possible arc length is ............. (Rounded off to two decimal places)
In a direct current arc welding, the voltage \( V \) (in volt) is related to the arc length \( l \) (in cm) as
\[
V = 30 + 30l.
\]
The open circuit voltage is 80 volts. The maximum possible arc length is ............. (Rounded off to two decimal places)
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In arc welding, the relation between voltage and arc length helps in determining the optimal settings for the welding process. Always solve for the variable in question using the provided equation.
Updated On: Mar 12, 2026
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Verified By Collegedunia
Correct Answer: 1.65
Solution and Explanation
Given the relation \( V = 30 + 30l \) and the open circuit voltage \( V = 80 \) volts, we can substitute into the equation:
\[
80 = 30 + 30l.
\]
Solving for \( l \), we get:
\[
30l = 80 - 30 = 50,
\]
\[
l = \frac{50}{30} = 1.6667.
\]
Thus, the maximum possible arc length is \( 1.67 \, {cm} \), rounded to two decimal places.
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