Question

В медном проводе длинной 2 метра и площадью поперечного сечения 0,4 мм2 идет ток. При этом в каждую секунду выделяется теплота 0,35 Дж. Сколько электронов проходит через поперечное сечение этого проводника за время 1 с ?

Answer 1

Закон Джоуля-Ленца - Q=I^2*R*t(1)

I=q/t

из (1) $I=\sqrt{Q/Rt}$

R=ρl/S

$I=\sqrt{QS/plt}$

$q/t=\sqrt{QS/plt}$

$q=\sqrt{QS/plt}*t$

Заряд одного электрона - 1,6 *10^-19 Кл

Чтобы найти количество электронов, нужно q/1,6 *10^-19

Answer 2

Calculation of the number of electrons passing through the cross-sectional area of the conductor in 1 second

To calculate the number of electrons passing through the cross-sectional area of the conductor in 1 second, we need to use the formula:

Q = I * t * e

Where: - Q is the total charge passing through the cross-sectional area of the conductor - I is the current flowing through the conductor - t is the time for which the current flows - e is the elementary charge, which is approximately 1.6 x 10^-19 Coulombs

Given: - Length of the conductor (L) = 2 meters - Cross-sectional area of the conductor (A) = 0.4 mm^2 = 0.4 x 10^-6 m^2 - Heat generated per second (H) = 0.35 Joules

To find the current (I), we can use Ohm's Law:

I = V / R

Where: - V is the voltage across the conductor - R is the resistance of the conductor

The resistance (R) can be calculated using the formula:

R = ρ * (L / A)

Where: - ρ is the resistivity of the material

Unfortunately, the resistivity (ρ) of the material is not provided in the question or the search results. Therefore, we cannot calculate the exact number of electrons passing through the cross-sectional area of the conductor.