The electric potential in a region is represented as $V = 2x + 3y -z$ ; then the expression of electric field strength is

Two metal pieces having a potential difference of $800 \;V$ are $0.02\; m$ apart horizontally. A particle of mass $1.96 \times 10^{-15} \;kg$ is suspended in equilibrium between the plates. If $e$ is the elementary charge, then charge on the particle is

The potential at a point $x$ (measured in $μ\ m$) due to some charges situated on the $ x$-axis is given by $V(x)$ =$\frac{{20}}{{{x^2} - 4}}$ $volt$ The electric field $E$ at $x = 4\ μ m$ is given by

In a certain reglon of space with volume $0.2\, m ^{3}$ the electric potential is found to be $5\, V$ throughout. The magnitude of electric field in this region is ______ $N/C$

The variation of potential with distance $x$ from a fixed point is as shown in figure. The electric field at $x =13\,m$ is......$volt/meter$

In a certain region of space, variation of potential with distance from origin as we move along $x$-axis is given by $V=8 x^2+2$, where $x$ is the $x$-coordinate of a point in space. The magnitude of electric field at a point $(-4,0)$ is .......... $V / m$