1
$\overrightarrow{E}={{۱۰}^{۳}}(۲۱\overrightarrow{i}+۱۲\overrightarrow{j})$
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2
$\overrightarrow{E}=-{{۱۰}^{۳}}(۲۱\overrightarrow{i}+۴\overrightarrow{j})$
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3
$\overrightarrow{E}={{۱۰}^{۳}}(۱۸\overrightarrow{i}-۱۲\overrightarrow{j})$
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4
$\overrightarrow{E}=-{{۱۰}^{۳}}(۶\overrightarrow{i}+۹\overrightarrow{j})$
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خطا
$E=K\frac{\left| q \right|}{{{r}^{2}}}$ ${{E}_{1}}=9\times {{10}^{9}}\times \frac{4\times {{10}^{-6}}}{{{3}^{2}}}=4\times {{10}^{3}}\frac{N}{C}$ ${{E}_{2}}=9\times {{10}^{9}}\times \frac{8\times {{10}^{-6}}}{{{2}^{2}}}=18\times {{10}^{3}}\frac{N}{C}$ ${{E}_{3}}=9\times {{10}^{9}}\times \frac{3\times {{10}^{-6}}}{{{3}^{2}}}=3\times {{10}^{3}}\frac{N}{C}$ $\overrightarrow{E}=(-{{E}_{2}}-{{E}_{3}})\overrightarrow{i}-{{E}_{1}}\overrightarrow{j}=-{{10}^{3}}(21\overrightarrow{i}+4\overrightarrow{j})\frac{N}{C}$ صفحهٔ 16 کتاب