Electrostatics Mock Tests

Two point charges +2 μC and +8 μC are placed 12 cm apart. The point where the electric field is zero is at a distance of: from the +2 μC charge

Two point charges +4q and +q are placed 12 m apart. A third charge Q is to be placed on the line joining them such that the system is in equilibrium. The distance of charge Q from +4q is:

Two point charges +3 μC and −3 μC are placed 2 mm apart forming an electric dipole. The electric field at a point on the axial line at distance 20 cm from the center is approximately in the direction:

A capacitor of capacitance C is charged to a potential V. It is then disconnected from the battery and connected across an uncharged capacitor of capacitance 2C. The final potential difference across the combination is:

An electric dipole of moment p is placed in a uniform electric field E. The work done in rotating the dipole from angle 0 degrees (stable equilibrium) to 180 degrees (unstable equilibrium) is:

Two identical capacitors of capacitance C each are connected in series to a battery of emf ε. A dielectric slab of constant K is now inserted between the plates of the first capacitor. The ratio of the new potential difference across C₁ to that across C₂ is:

Two identical capacitors each of capacitance C are connected in parallel. The combination is charged to a potential V and then disconnected. If one capacitor is reversed and connected again, the final common potential is:

Two capacitors C1 = 2 muF and C2 = 4 muF are connected in series. The equivalent capacitance is: