MCQ
An electron and a proton are both released from rest $1$ meter from a large stationary negative charge, considering only the force from the large stationary negative charge on the proton and electron. Which of the following is true?
  • A
    Neither the proton nor the electron will accelerate.
  • B
    The initial acceleration of the proton is greater.
  • C
    Both the electron and proton have the same non$-$zero initial acceleration.
  • The initial acceleration of the electron is greater.

Answer

Correct option: D.
The initial acceleration of the electron is greater.

The magnitude of electric force between electron and proton is given by $\text{F}=\frac{1}{4\pi\in_0}\frac{\text{e(-e)}}{\text{d}^2}$
The force on each of them is equal in magnitude and is attractive.
The acceleration of a species is given by $\text{a}=\frac{\text{F}}{\text{m}}$

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