Electric Charge...

The potential at a point $$(x, 0, 0)$$ is given by $$V = \left(\dfrac{1000}{x} + \dfrac{1500}{x^2} + \dfrac{500}{x^3}\right)$$. The intensity of the electric field at $$x = 1$$ will be

Six charges of equal magnitude, $$3$$ positive and $$3$$ negative are to be placed on $$PQRSTU$$ corners of a regular hexagon, such that field at the center is double that of what it would have been if only one $$+$$ve charges is placed at $$R$$

Consider a triangular surface whose vertices are three points having co-ordinate A ( 2a, 0, 0 ), B(0, a, 0), C(0, 0, a). If there is a uniform electric field $$E_0\hat{i} + 2 E_0\hat {j} + 3 E_0 \hat {k} $$ then flux linled to triangular surface ABC is:

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A field normal to the plane of a circular wire n turns and radius r which carries a current I is measured on the axis of the coil at small h distance h from the centre of the coil. This is smaller than the field at the centre by a friction ____

A particle of mass $$m$$ and carrying charge $$-{q}_{1}$$ is moving around a charge $$+{q}_{2}$$ along a circular path of radius $$r$$. Find period of revolution of the charge $$-{q}_{1}$$

A charge particle $${q}_{1}$$ is at position $$(2, -1, 3)$$. The electrostatic force on another charged particle $${q}_{2}$$ at $$(0, 0, 0)$$ is:

Point charges $$+4q$$, $$-q$$ and $$+4q$$ are kept on the $$x-$$axis at points $$x=0,x=a$$ and $$x=2a$$, respectively, then:

A particle of charges $${q}_{0}$$ is moved around a charge $$+q$$ along the semicircle path of radius $$r$$ from A to B (see figure). The work done by the Coulomb force is

Two positive ions, each carrying a charge q are separated by a distance d. If $$F$$ is the force of repulsion between the ions, the number of electrons missing from each ion will be (c being, the charge of an electron).

Two small balls,each having equal positive change $$Q$$ are suspended by two insulating strings of equal length L from a hook fixed to a stand. If the whole set up is transferred to a satellite in orbit around the earth, the tension in equilibrium in each string is equal to: