A constantan wire has a cross sectional area of 4 x 10-8m2 and a resistivity of 1.1 x 10-6\(\Omega\)m. If a resistor of resistance 11\(\Omega\) is to be mad...
A constantan wire has a cross sectional area of 4 x 10-8m2 and a resistivity of 1.1 x 10-6\(\Omega\)m. If a resistor of resistance 11\(\Omega\) is to be made from this wire, calculate the length of the wire required
Answer Details
The resistance of a wire is directly proportional to its length and resistivity, and inversely proportional to its cross-sectional area. This relationship is expressed by the formula: Resistance = (Resistivity x Length) / Cross-sectional area To calculate the length of the wire required to make a resistor of 11\(\Omega\), we can rearrange this formula to solve for length: Length = (Resistance x Cross-sectional area) / Resistivity Substituting the given values, we get: Length = (11\(\Omega\) x 4 x 10-8m2) / 1.1 x 10-6\(\Omega\)m Simplifying the expression by canceling units, we get: Length = 0.4m Therefore, the length of the constantan wire required to make a resistor of 11\(\Omega\) is 0.4 meters.