Đáp án:
\(\begin{align}
& A'=3,{{47.10}^{-18}}J \\
& v=3,{{7.10}^{6}}m/s \\
\end{align}\)
Giải thích các bước giải:
Câu 3:
\(d=0,3cm;A=2,{{6.10}^{-18}}J\)
a> Ta có:
\(A=qE.d\Rightarrow E=\dfrac{2,{{6.10}^{-18}}}{{{1.6.10}^{-19}}.0,{{3.10}^{-2}}}=5416,7V/m\)
d'=0,4cm
\(A'=\left| q \right|.E.d'=1,{{6.10}^{-19}}.5416,7.0,{{4.10}^{-2}}=3,{{47.10}^{-18}}J\)
b> Gia tốc
\(a=\dfrac{\left| q \right|.E}{m}=\dfrac{1,{{6.10}^{-19}}.5416,7}{9,{{1.10}^{-31}}}=9,{{5.19}^{14}}m/{{s}^{2}}\)
Vận tốc:
\({{v}^{2}}=2a.S\Rightarrow v=\sqrt{2.9,{{52.10}^{14}}.(0,3+0,4){{.10}^{-2}}}=3,{{7.10}^{6}}m/s\)
