why do all materials have resistance?

Question

why do all materials have resistance?

explain briefly. I know that all materials have atoms but how does the material resist force etc. involving atoms?

explain briefly. I know that all materials have atoms but how does the material resist force etc. involving atoms? resistance in general.

Answer 1

Not exactly true; superconductors have zero resistance. However, the temperatures required for superconductivity are much lower than normal temperatures you experience on a daily basis. This page lists some superconducting materials and they're critical temperatures (the temperature at which they become superconducting):

http://scienceworld.wolfram.com/physics/Superconductivity.html

You can think of resistance as the electrical analog of drag (air resistance).

Example: Compare the differential equations

Mechanical: Mass-spring system
m*d²x/dt² + b*dx/dt + k*x = 0

*x = displacement from equilibrium position
*m = mass
*b = damping coefficent
*k = spring constant

Electrical: RLC loop
L*d²q/dt² + R*dq/dt + (1/C)*q = 0

*q = charge
*L = inductance of inductor
*R = resistance of resistor
*C = capacitance of capacitor

The middle terms impede the motion, or "damp" the system.
Just as drag slows down the motion of a body, resistance impedes the motion of electrons in a material.

Answer 2

Electrical conduction is the displacement of free charges in a material. The charge carriers can be electrons, positrons (rare), holes (the absence of an electron in a semiconductor), or ions of either polarity. In materials with high resistance, virtually all of the possible carriers are bound. Conductors have free carriers. In the case of semiconductors the carriers are almost free and can be promoted to the conduction band by thermal energy or by electrical excitation (a photon, for example). Free carriers have a finite mean free path in ordinary materials. The carrier is scattered by a variety of processes, the most important being thermal vibrations (phonons) and crystal defects (dislocations). In each scattering event, the electron momentum is changed and this scattering is the underlying cause for electrical resistance. The conductivity of a material increases as the mean free path of a carrier increases, so crystalline materials tend to be better conductors than amorphous materials. In superconductors, the mean free path is infinite and the resistance is zero.

Answer 3

if u push the wall ---does it move?
no ,...because of friction

just as so the charges of current r too small to really affect the the atoms of the conductor. they keep bouncing on n off. and keep spending their energy uselessly. hence this uselessly done work is due to resistance of the conductor
energy spent = resistance.

having no resistance would mean that conductors r absolutely smooth, and the charges themselves move in an absolutely straight path without colliding, this is practically impossible

hence all materials have some amount of resistance

if u need more hlp, mail me

Answer 4

In conductors, when current flows i.e. flow of electrons actually they move from outer shells of different atoms during this they may collide with the existing electronics of atoms, nucleus of atoms, vibrating electrons so due to this they observe hindrance in the path.
In insulators/dielectric materials there are not ample amount of free electrons as just in conductor. So the force required to remove the electrons from its parent atom is more. As there are no such free carrier which can transport/transfer from one atom to another atoms in the outer most shell so due to this also such material offers greater resistance.

Answer 5

material have resistance because in it atoms presents , but they are in (always) vibrating motion . So when corrent in the form electron flows through it then electrons collide on vibrating atoms,so electrns are get resistance to flo current by these vibrating atoms, so material have resistance

Answer 6

Magnetic, molecular, or polarity resistance?

Answer 7

everything is built from atoms, and these are electrical in nature.
So everything has resistance.

Answer 8

because of subatomic structures