A charged particle of charge $Q $ is held fixed and another charged particle of mass $m$ and charge $q$ (of the same sign) is released from a distance $r.$ The impulse of the force exerted by the external agent on the fixed charge by the time distance between $Q$ and $q$ becomes $2r$ is
A charged particle of charge $Q $ is held fixed and another charged particle of mass $m$ and charge $q$ (of the same sign) is released from a distance $r.$ The impulse of the force exerted by the external agent on the fixed charge by the time distance between $Q$ and $q$ becomes $2r$ is
- A
$\sqrt {\frac{{Qq}}{{4\pi { \in _0}mr}}} $
- B
$\sqrt {\frac{{Qqm}}{{4\pi { \in _0}r}}} $
- C
$\sqrt {\frac{{Qqm}}{{\pi { \in _0}r}}} $
- D
$\sqrt {\frac{{Qqm}}{{2\pi { \in _0}r}}} $
Similar Questions
A particle of charge $q$ and mass $m$ is subjected to an electric field $E = E _{0}\left(1- ax ^{2}\right)$ in the $x-$direction, where $a$ and $E _{0}$ are constants. Initially the particle was at rest at $x=0 .$ Other than the initial position the kinetic energy of the particle becomes zero when the distance of the particle from the origin is
A particle of charge $q$ and mass $m$ is subjected to an electric field $E = E _{0}\left(1- ax ^{2}\right)$ in the $x-$direction, where $a$ and $E _{0}$ are constants. Initially the particle was at rest at $x=0 .$ Other than the initial position the kinetic energy of the particle becomes zero when the distance of the particle from the origin is
- [JEE MAIN 2020]
What is the potential energy of the equal positive point charges of $1\,\mu C$ each held $1\, m$ apart in air
What is the potential energy of the equal positive point charges of $1\,\mu C$ each held $1\, m$ apart in air
On moving a charge of $20$ coulombs by $2 \;cm , 2 \;J$ of work is done, then the potential difference between the points is (in $volt$)
On moving a charge of $20$ coulombs by $2 \;cm , 2 \;J$ of work is done, then the potential difference between the points is (in $volt$)
- [AIEEE 2002]
A block of mass $m$ containing a net negative charge $-q$ is placed on a frictionless horizontal table and is connected to a wall through an unstretched spring of spring constant $k$ as shown. If horizontal electric field $E$ parallel to the spring is switched on, then the maximum compression of the spring is :-
A block of mass $m$ containing a net negative charge $-q$ is placed on a frictionless horizontal table and is connected to a wall through an unstretched spring of spring constant $k$ as shown. If horizontal electric field $E$ parallel to the spring is switched on, then the maximum compression of the spring is :-
An electron with an initial speed of $4.0 \times 10^6 \,ms ^{-1}$ is brought to rest by an electric field. The mass and charge of an electron are $9 \times 10^{-31} \,kg$ and $1.6 \times 10^{-19} \,C$, respectively. Identify the correct statement.
An electron with an initial speed of $4.0 \times 10^6 \,ms ^{-1}$ is brought to rest by an electric field. The mass and charge of an electron are $9 \times 10^{-31} \,kg$ and $1.6 \times 10^{-19} \,C$, respectively. Identify the correct statement.
- [KVPY 2013]