Physics Test 27...

Two point charges 3 × 10^-6 C and 8 × 10^-6 C repel each other by a force of 6 × 10^-3 N. If each of them is given an additional charge of -6 × 10^-6 C, then the force between them will be

Three charges 1 μC, 1μC and 2 μC are respectively kept at the vertices A, B and C of an equilateral triangle ABC of side 10 cm. The resultant force on the charge at C is

If the inward flux and outward electric flux from a closed surface respectively are 8 × 10³ units and 4 × 10³ units, then what is the net charge inside the closed surface?

A metallic solid sphere is placed in a uniform electric field as shown. Which path will the lines of force follow?

An electric dipole placed in a non-uniform electric field experiences

Assertion (A): In a cavity in a conductor, the electric field is zero.

Reason (R): Charges in a conductor reside only at its surface.

Assertion : The Coulomb force is the dominating force in the universe.

Reason : The Coulomb force is weaker than the gravitational force.

The potential of the electric field produced by a point charge at any point (x, y, z) is given by V = 3x² + 5, where x, y and z are in metres and V is in volts. The intensity of the electric field at (–2, 1, 0) is

A capacitor of capacitance C₁ is charged by connecting it to a battery. The battery is then removed and this capacitor is connected to a second uncharged capacitor of capacitance C₂. If the charge gets distributed equally on the two capacitors, then the ratio of the total energy stored in the capacitors, after connection to the total energy stored in them before connection, is

Assertion: A parallel plate capacitor is charged by a battery. The battery is then disconnected. If the distance between the plates is increased, then the energy stored in the capacitor will decrease.

Reason: Work has to be done to increase the separation between the plates of a charged capacitor.