The electric potential $V$ at any point $(x, y, z),$ all in metres in space is given by $V = 4x^2$ volt. The electric field at the point $(1, 0, 2)$ in volt/meter, is 
AIPMT 2011, Easy
Download our app for free and get startedPlay store
$\vec{E}=-\bar{\nabla} V$

where $\bar{\nabla}=\hat{i} \frac{\partial}{\partial x}+\hat{j} \frac{\partial}{\partial y}+\hat{k} \frac{\partial}{\partial z}$

$\therefore \quad \vec{E}=-\left[\hat{i} \frac{\partial V}{\partial x}+\hat{j} \frac{\partial V}{\partial y}+\hat{k} \frac{\partial V}{\partial z}\right]$

Here, $V=4 x^{2} \quad \therefore \quad \vec{E}=-8 x \hat{i}$

The electric field at point $(1,0,2)$ is

$\vec{E}_{(1,0,2)}=-8 \hat{i}\,Vm^{-1}$

So electric field is along the negative $X$ -axis.

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    A neutral spherical copper particle has a radius of $10 \,nm \left(1 \,nm =10^{-9} \,m \right)$. It gets charged by applying the voltage slowly adding one electron at a time. Then, the graph of the total charge on the particle versus the applied voltage would look like
    View Solution
  • 2
    A sheet of aluminium foil of negligible thickness is introduced between the plates of a capacitor. The capacitance of the capacitor
    View Solution
  • 3
    Work done by an external agent in separating the parallel plate capacitor is
    View Solution
  • 4
    In the circuit shown in figure $C_1 = C_2 = 2$ $\mu F$. Then charge stored in
    View Solution
  • 5
    If the electric potential at any point $(x, y, z) \,m$ in space is given by $V =3 x ^{2}$ volt. The electric field at the point $(1,0,3) \,m$ will be ............
    View Solution
  • 6
    A conductor with a positive charge
    View Solution
  • 7
    A point charge is surrounded symmetrically by six identical charges at distance $r$ as shown in the  figure. How much work is done by the forces of electrostatic repulsion when the point charge $q$ at the centre is removed at infinity 
    View Solution
  • 8
    In space of horizontal $EF$ ($E = (mg)/q$) exist as shown in figure and a mass $m$ attached at the end of a light rod. If mass $m$ is released from the position shown in figure find the angular velocity of the rod when it passes through the bottom most position
    View Solution
  • 9
    Aspherical shell with an inner radius $'a'$ and an outer radius $'b' $ is made of conducting material. Apoint charge $+Q$ is placed at the centre of the spherical shell and a total charge $- q $ is placed on the shell.

    Assume that the electrostatic potential is zero at an infinite distance from the spherical shell. The electrostatic potential at a distance $R$ $(a < R < b)$ from the centre of the shell is (where $K = $ $\frac{1}{{4\pi {\varepsilon _0}}}$)

    View Solution
  • 10
    Two tiny electric dipoles of dipole moment $P_1$ and $P_2$ are placed $'r'$ distance coaxially find magnitude of electrostatic force between them.
    View Solution