MCQ
If an electron moves from rest from a point at which potential is $50\, volt$ to another point at which potential is $70\, volt$, then its kinetic energy in the final state will be
- A$3.2 × 10^{-10} J$
- ✓$3.2 × 10^{-18} J$
- C$1\, N$
- D$1 \,dyne$
✓
Answer
Correct option: B.
$3.2 × 10^{-18} J$
b
(b) $\,{\rm{K}}{\rm{.E}}{\rm{.}}\, = {q_0}({V_A} - {V_B}) = 1.6 \times {10^{ - 19}}(70 - 50) = 3.2 \times {10^{ - 18}}J$
(b) $\,{\rm{K}}{\rm{.E}}{\rm{.}}\, = {q_0}({V_A} - {V_B}) = 1.6 \times {10^{ - 19}}(70 - 50) = 3.2 \times {10^{ - 18}}J$
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