The document asks about the resistance of 235m of 2.5mm^2 aluminum cable and calculates it to be 2.632Ω. It then asks about the length of a 1.5mm^2 copper cable with a resistance of 4.5Ω, rearranging the resistance formula to calculate the length as 390.625m.

1. What is the resistance of 235m of 2.5mm 2 aluminium cable? ( p alluminuim = 2.8x10 -8 )

2. What is the resistance of 235m of 2.5mm 2 aluminium cable? ( p alluminuim = 2.8x10 -8 ) R= p l / a

3. What is the resistance of 235m of 2.5mm 2 aluminium cable? ( p alluminuim = 2.8x10 -8 Ω/m ) R= p l / a R = 2.8x10 -8 Ω/m x 235m/ 2.5 x 10 -6 m 2 * *We must convert mm 2 to m 2 1mm 2 = 1 x 10 -6 m 2

4. What is the resistance of 235m of 2.5mm 2 aluminium cable? ( p alluminuim = 2.8x10 -8 Ω/m ) R= p l / a R = 2.8x10 -8 Ω/m x 235m/ 2.5 x 10 -6 m 2 R = 2.632Ω

5. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m )

6. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a

7. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject

8. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject Multiple both sides by a R x a = p l /a x a

9. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject Multiple both sides by a R x a = p l /a x a R x a = p l

10. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject Multiple both sides by a R x a = p l /a x a R x a = p l Divide both sides by p

11. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject Multiple both sides by a R x a = p l /a x a R x a = p l Divide both sides by p (R x a) / p = l

12. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject Multiple both sides by a R x a = p l /a x a R x a = p l Divide both sides by p (R x a) / p = l Now solve

13. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject Multiple both sides by a R x a = p l /a x a R x a = p l Divide both sides by p (R x a) / p = l Now solve l = (4.5 Ω x 1.5 x 10 -6 mm2 )/ 1.728x10-8Ω/m

14. How long is a copper cable that is 1.5 mm2 and has a resistance of 4.5 Ω ? ( p copper = 1.728x10 -8 Ω/m ) R= p l /a We must rearrange the formula to make l the subject Multiple both sides by a R x a = p l /a x a R x a = p l Divide both sides by p (R x a) / p = l Now solve l = (4.5 Ω x 1.5 x 10 -6 mm2 )/ 1.728x10 -8 Ω/m l = 390.625m