Question

Какое количество теплоты выделится за 40 мин в медном проводнике площадью поперечного сечения 1,5 мм2 и длиной 3 М, проходящем электрический ток к обогревателю? Сила тока в цепи 5 А. Удельное сопротивление меди 0,017 Ом*мм2/м.

Answer 1

Q = J^2*R*t.
R = p*L/S.
R = 0.017*3/1.5 = 0,034 Ом. 
Q = 5^2*0,034*2400 = 2040 Дж.

Answer 2

Calculating Heat Generated in a Copper Conductor

To calculate the amount of heat generated in a copper conductor when an electric current passes through it, we can use the formula:

Q = I^2 * R * t

Where: - Q = heat generated (in joules) - I = current (in amperes) - R = resistance (in ohms) - t = time (in seconds)

Given: - Current (I) = 5 A - Resistance (R) = 0.017 Ohm*mm^2/m - Time (t) = 40 minutes = 2400 seconds - Cross-sectional area (A) = 1.5 mm^2 - Length (L) = 3 m

First, we need to calculate the resistance of the copper conductor using the given parameters.

Calculating Resistance of the Copper Conductor

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

R = (ρ * L) / A

Where: - ρ = resistivity of the material (in ohm*mm^2/m) - L = length of the conductor (in meters) - A = cross-sectional area of the conductor (in mm^2)

Substitute the given values: - ρ = 0.017 Ohm*mm^2/m - L = 3 m - A = 1.5 mm^2

R = (0.017 * 3) / 1.5

R = 0.034 Ohms

Calculating Heat Generated

Now, we can use the formula to calculate the heat generated (Q):

Q = I^2 * R * t

Substitute the given values: - I = 5 A - R = 0.034 Ohms - t = 2400 seconds

Q = 5^2 * 0.034 * 2400

Q = 5^2 * 0.034 * 2400 Q = 425.25 Joules

Therefore, the amount of heat generated in the copper conductor over 40 minutes when a current of 5 A passes through it is approximately 425.25 Joules.