Предмет: Физика, автор: Vi71

По вольфрамовой проволоке протекает электрический ток. Длина проволоки – 4 м, сила тока составляет 0,05 А. Напряжение, под которым находится данный проводник, составляет 5 В. Необходимо определить величину площади поперечного сечения.

Ответы

Автор ответа: tatanovsasha

$R= \frac{pl}{S} = \frac{U}{I}$

$S= \frac{Ipl}{U} = \frac{0,05*0,055*4}{5} =0,0022mm^2$

Автор ответа: Polinko2000

R=p(ро)×l÷S
S=р(ро)×l÷R
R=U÷I
R=5B÷0,05А=100 Ом
ро для вольфрама = 0,055 Ом*мм²÷м
S=0,055×4м÷100 Ом=0,0022 м

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