Basic Resistivity calculations

a 2.5mm² copper conductor has a resistivity value of 17.2μΩ per mm, and is 25 metres long. Calculate its total resistance value
1. 0.172Ω
2. 0.000172Ω
3. 1.72Ω
4. 0.0172Ω
a 16mm² aluminium conductor has a resistivity value of 28μΩ per mm, and is 60 metres long. Calculate its total resistance value
1. 0.11Ω
2. 1.11Ω
3. 105Ω
4. 0.011Ω
Which material has the HIGHEST resistivity value from the following choices?
1. aluminium
2. steel
3. copper
4. silver
Which material has the LOWEST resistivity value from the following choices?
1. aluminium
2. copper
3. steel
4. Brass
a 25mm² aluminium conductor has a resistivity value of 28nΩ per metre, and is 45 metres long. Calculate its total resistance value
1. 0.05Ω
2. 0.5Ω
3. 5Ω
4. 0.005Ω
a copper conductor has a resistivity value of 17.2nΩ per metre and an area of 6mm². If the length is 28 metres calculate the total resistance
1. 0.08Ω
2. 0.8Ω
3. 0.008Ω
4. 8Ω
Which one of the following Resistivity (ρ) value 'conversions' is correct?
1. 17.2 nano ohm millimeters = 17.2 micro ohm metres
2. 17.2 nano ohm millimeters = 172 micro ohm metres
3. 17.2 nano ohm millimeters = 0.172 micro ohm metres
4. 17.2 nano ohm millimeters = 1.72 micro ohm metres
a 4mm² copper conductor has a resistivity value of 17.2μΩ per mm, and is 35 metres long. Calculate its total resistance value
1. 0.151Ω
2. 0.000151Ω
3. 1.51Ω
4. 0.0151Ω
a 50mm² aluminium conductor has a resistivity value of 28nΩ per metre, and is 30 metres long. Calculate its total resistance value
1. 0.017Ω
2. 0.17Ω
3. 1.7Ω
4. 0.0017Ω
a copper conductor has a resistivity value of 17.2nΩ per metre and an area of 1.5mm². If the length is 33 metres calculate the total resistance
1. 0.38Ω
2. 0.038Ω
3. 0.25Ω
4. 2.5Ω
Which one of the following Resistivity (ρ) value 'conversions' is correct?
1. 17.2 x10^-6 Ω per mm = 17.2 x10^-9 Ω per m
2. 17.2 x10^-6 Ω per mm = 1.72 x10^-9 Ω per m
3. 17.2 x10^-6 Ω per mm = 0.172 x10^-9 Ω per m
4. 17.2 x10^-6 Ω per mm = 0.0172 x10^-9 Ω per m
Which one of the following Resistivity (ρ) value 'conversions' is correct?
1. 28 x10^-6 Ω per mm = 28 x10^-9 Ω per m
2. 28 x10^-6 Ω per mm = 2.8 x10^-9 Ω per m
3. 28 x10^-6 Ω per mm = 0.28 x10^-9 Ω per m
4. 28 x10^-6 Ω per mm = 0.028 x10^-9 Ω per m
Which one of the following Resistivity (ρ) value 'conversions' is correct?
1. 28 nano ohm meters = 28 micro ohm millimetres
2. 28 nano ohm meters = 280 micro ohm millimetres
3. 28 nano ohm meters = 0.28 micro ohm millimetres
4. 28 nano ohm meters = 2.8 micro ohm millimetres
Identify the correct resistivity formula for calculating Resistance (R).
1. R = ρ l / a
2. R = ρ / l a
3. R = l / ρ a
4. R = ρ a / l
a 35mm² copper conductor has a ρ value of 17.8x10^-9Ω per metre and is 77 metres long. Calculate its total resistance
1. 0.04Ω
2. 4Ω
3. 0.28Ω
4. 0.028Ω
a 6mm² copper conductor has a ρ value of 17.8x10^-6Ω per mm and is 42 metres long. Calculate its total resistance
1. 0.12Ω
2. 1.2Ω
3. 0.18Ω
4. 0.018Ω
a 50mm² aluminium conductor has a ρ value of 28x10^-6Ω per mm and is 105 metres long. Calculate its total resistance
1. 0.06Ω
2. 0.6Ω
3. 6Ω
4. 0.006Ω
a 0.08Ω copper conductor has a ρ value of 17.8nΩ per m and c.s.a (cross sectional area) of 16mm². Calculate its length expressed in metres
1. 71.91 metres
2. 55.86 metres
3. 89 metres
4. 55.5 metres
a 0.0554Ω aluminium conductor has a ρ value of 28μΩ per mm and is 99 metres long. Calculate its c.s.a (cross sectional area) (a)
1. 50mm²
2. 25mm²
3. 35mm²
4. 16mm²
identify the correctly transposed (rearranged) formula to find length (l)
1. Length = R a / ρ
2. Length = ρ a / R
3. Length = R / ρ a
4. Length = a / ρ R
identify the correctly transposed (rearranged) formula to find area (a)
1. area (a) = ρ l / R
2. area (a) = ρ R / l
3. area (a) = R / ρ l
4. area (a) = l / ρ R
identify the correctly transposed (rearranged) formula to find the resistivity value (ρ)
1. ρ = R a / l
2. ρ = R l / a
3. ρ= R / l a
4. ρ = l a / R
identify the correct area conversion
1. 1.5mm² = 1.5 x10^-6m²
2. 1.5mm² =1.5 x10^-4m²
3. 1.5mm² = 1.5 x10^-3m²
4. 1.5mm² = 1.5 x10³m²
Identify the correct length conversion
1. 47 metres = 47 x10³ mm
2. 47 metres = 47 x10² mm
3. 47 metres = 47 x10^-2 mm
4. 47 metres = 47 x10^-3 mm
Identify the correct length conversion
1. 27650 mm = 27650x10^-3 m
2. 27650 mm = 27650x10³ m
3. 27650 mm = 27650x10⁶ m
4. 27650 mm = 27650x10^-6 m
Identify the correct length conversion
1. 44,550 mm = 44.55 m
2. 44,550 mm = 4.455 m
3. 44,550 mm = 445.5 m
4. 44,550 mm = 4455.0 m

Basic Resistivity calculations

Basic Resistivity Calculations - calculating resistance (R), Length (L) and c.s.a (area), basic formula transposition and basic unit conversions: 10 basic questions from a big bank of questions© K.Brown 2025

Basic Resistivity Calculations - calculating resistance (R), Length (L) and c.s.a (area), basic formula transposition and basic unit conversions: 10 basic questions from a big bank of questions
© K.Brown 2025