The diagram shows three infinitely long uniform line charges placed on the $X, Y $ and $Z$ axis. The work done in moving a unit positive charge from $(1, 1, 1) $ to $(0, 1, 1) $ is equal to
$(\lambda\ ln \ 2) / 2\ \pi \varepsilon_0$
$(\lambda\ ln\ 2)\ /\pi \varepsilon_0$
$(3\ \lambda\ ln \ 2)\ / 2\ \pi \varepsilon_0$
None
A ball of mass $1\, g$ and charge ${10^{ - 8}}\,C$ moves from a point $A$. where potential is $600\, volt$ to the point $B$ where potential is zero. Velocity of the ball at the point $B$ is $20\, cm/s$. The velocity of the ball at the point $A$ will be
The charge $q$ is fired towards another charged particle $Q$ which is fixed, with a speed $v$. It approaches $Q$ upto a closest distance $r$ and then returns. If $q$ were given a speed $2 v$, the closest distance of approach would be
In the figure the charge $Q$ is at the centre of the circle. Work done is maximum when another charge is taken from point $P$ to
Charges $+q$ and $-q$ are placed at points $A$ and $B$ respectively which are a distance $2\,L$ apart, $C$ is the midpoint between $A$ and $B.$ The work done in moving a charge $+Q$ along the semicircle $CRD$ is
A particle of mass $100\, gm$ and charge $2\, \mu C$ is released from a distance of $50\, cm$ from a fixed charge of $5\, \mu C$. Find the speed of the particle when its distance from the fixed charge becomes $3\, m$. Neglect any other force........$m/s$