Question

What happensort to resistance of the conductor
1. When temperature is increased
2. When the length is doubled
3. When area of cross section is increased

Answer 1

1 If the temperature is increased: the reactant particles move more quickly. they have more energy. the particles collide more often, and
more of the collisions result in a reaction.

2 R = pl/A, where R is resistance, p is the material's resistance in ohms, l is the length, and A is the cross sectional area in m^2. As a wire gets longer its resistance increases, and as it gets thinner its resistance also increases because its cross sectional area decreases.

3 A prism is a shape with a constant cross section, in other words the cross-section looks the same anywhere along the length of the solid (examples: cylinder, cuboid). The volume of a prism = the area of the cross-section × the length.

Answer 2

1.
R = ml / n e^2 ( tow ) A
R inversaly proportional to the ( tow )

The value of the Electrical Resistance R increase with rise of Temperature
number density n of free electron does not change with temperature but an increase in temperature increase in amplitude of vibration of lattice ions of the the metal ( Conductor ) and thermal speed of the electron which act as carriers of current . Due to it , the collision of free electrons with ions /atoms while drifting towards the positive end of the conductor become more frequent , resulting in decrease in relaxation time (tow ) .

When the length of the conductor is doubkef then R increase 4times
R'= 4 R
see the proof
l'=2 l

R= p l/A

V= l xA = l' x A'

A'= A/2

R' = p l'/ A'

R' = p 2 l x 2/A

R'= 4 p l/A

R'= 4 R

3)

R is inversaly proportional to the A
that's why when we increase are no electrin passing got more space and R is decreased .
________________☆Physics______