why is that electrical resistance is important ? how dose it varying with the length of a wire?

Answer 1

its important because it takes energy to make that electricity move. resistance is caused when a wire is not pure or when it goes thru a load. when it does it produces either heat or light. the length of wire is not as important really as the thickness because electrons have an easier time with thicker wire because they dance across the top not actually thru the metal of the wire. to make electricity "flow" you have to overcome resistance

Answer 2

Electrical resistance is important becouse it take a part from the energy moving through it & change it to another thing (heat, light, ...etc)

It is varying with the length of wire becouse of resistivity
Resistivity: It is numerically equal to the resistance of a piece of a material one meter length and one squared meter cross-sectional area at constant temprature

Formual of resistivity:
Resistiviy = (R*L)/A
R: resistance of the material (wire)
L: Length of the wire
A: Cross-sectional area
We can see from the formula that resistivity is directly proportional to the length of the wire so it varys with it

i hope u got ur point from my explanation

Answer 3

electrical resistance is what causes light bulbs to light up because it creates photons of electrical light.