Consider a charged sphere of radius R with charge density f(r ) = e-r....
Given, charge density f(r ) = e
-rThis density depends only on the radius r and not (θ, φ) of spherical polar coordinates.
Therefore, the equipotential surfaces for this volume charge are spheres of different radii with potential decreasing radially outwards
is radially outwards). This means that V (r, θ, φ) decreases with radius. The gradient of a surface is in the direction along the maximum rate o f increase o f the function (here V (r, θ, φ)).
Therefore, gradient of the equipotential surfaces are radially inwards.
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Consider a charged sphere of radius R with charge density f(r ) = e-r....
Equipotential Surfaces:
Equipotential surfaces are surfaces in a region where the potential is constant. In the case of a charged sphere, the equipotential surfaces are spherical shells concentric with the sphere.
Charge Density:
The charge density of the sphere is given by f(r) = e^(-r), where r is the distance from the center of the sphere and e is a constant.
Gradient Vector:
The gradient vector of a scalar function represents the direction of the steepest increase of the function. In this case, the scalar function is the electric potential.
Direction of the Gradient Vector:
To determine the direction of the gradient vector, we need to consider the charge distribution and the electric potential.
Radial Inward Direction:
If the gradient vector points radially inwards, it would imply that the electric potential decreases as we move away from the center of the sphere. However, in the case of a charged sphere, the electric potential increases as we move away from the center. Therefore, the gradient vector cannot point radially inwards.
Radial Outward Direction:
Since the electric potential increases as we move away from the center of the sphere, the gradient vector must point radially outward. This is because the direction of the steepest increase in the potential is away from the center of the sphere.
Tangential Direction:
The gradient vector does not point tangentially in any direction. It represents the direction of the steepest increase of the potential, which is always radial.
Clockwise or Anti-clockwise Direction:
The gradient vector does not have a rotational component, so it does not have a specific clockwise or anti-clockwise direction.
Therefore, the correct answer is option 'B' - the gradient vector to the family of equipotential surfaces of this charged sphere points radially outward.