Electrostatics
Two charged particles having charge $$2.0\times 10^{-8}C$$ each are joined by an insulating string of length $$1m$$ and the system is kept on a smooth horizontal table. Find the tension in the string.
Two identical balls, each having a charge of $$2.00\times 10^{-7}$$C and a mass of $$100$$g, are suspended from a common point by two insulating strings each $$50$$ cm long. The balls are held at a separation $$5.0$$cm apart and the released. Find the components of the resultant force on it along and perpendicular to the string. Answer is to be obtained only for the instant just after the release.
Two charged particles having charge $$2.0\times 10^{-8}C$$ each are joined by an insulating string of length $$1m$$ and the system is kept on a smooth horizontal table. Find the tension in the string.
Two equal charges are placed at a separation of $$1.0$$m. What should be the magnitude of the charges so that the force between them equals the weight of a $$50$$ kg person?
Suppose all the electrons of $$100$$g water are lumped together to form a negatively charged particle and all the nuclei are lumped together to form a positively charged particle. If these two particles are placed $$10.0$$cm away from each other, find the force of attraction between them. Compare it with your weight.
Consider a gold nucleus to be a sphere of radius $$6.9$$ fermi in which protons and neutrons are distributed. Find the force of repulsion between two protons situated at largest separation. Why do these protons not fly aparat under this repulsion?
Suppose an attractive nuclear force acts between two protons which may be written as $$F=Ce^{-kr}/r^2$$. Suppose that $$k=1$$ $$fermi^{-1}$$ and that the repulsive electric force between the protons is just balanced by the attractive nuclear force when the separation is $$5$$ fermi. Find the value of C.
Three equal charges $$2.0\times 10^{-6}$$C each, are held fixed at the three corners of an equilateral triangle of side $$5$$cm. Find the Coulomb force experienced by one of the charges due to the rest two.
A hydrogen atom contains one proton and one electron. It may be assumed that the electron revolves in a circle of radius $$0.53$$ angstrom($$1$$ angstrom$$=10^{-10}$$m and is abbreviated as $$\overset{\bullet}{A}$$) with the proton at the centre. The hydrogen atom is said to be in the ground state in this case. Find the magnitude of the electric force between the proton and the electron of a hydrogen atom in its ground state.
Ten positively charged particles are kept fixed on the x-axis at points $$x=10$$cm, $$20$$cm, $$30$$cm, ...., $$100$$cm. The first particle has a charge $$1.0\times 10^{-8}$$C, the second $$8\times 10^{-8}$$C, the third $$27\times 10^{-8}$$C and so on. The tenth particle has a charge $$1000\times 10^{-8}$$C. Find the magnitude of the electric force acting on a $$1$$C charge placed at the origin.
Two identical pith balls are charged by rubbing against each other. They are suspended from a horizontal rod through two strings of length $$20$$cm each, the separation between the suspension points being $$5$$cm. In equilibrium, the separation between the balls is $$3$$ cm. Find the mass of each ball and the tension in the strings. The charge on each ball has a magnitude $$2.0\times 10^{-8}$$C.
Two small spheres, each having a mass of $$20$$g, are suspended from a common point by two insulating strings of length $$40$$cm each. The spheres are identically charged and the separation between the balls of equilibrium is found to be $$4$$cm. Find the charge on each sphere.