Three charges each equal to 2 μC are placed at the corners of an equilateral triangle. If force between any two charges is 2F, then the net force on either will be:
A charge q is placed at one corner of the cube. The electric flux passing through any one of its face is
A point charge +Q is placed in the vicinity of a conducting surface. Draw the electric field lines between the surface and the charge.
The charges on two spheres are +7mC and –5mC respectively. They experience a force F. If each of them is given an additional charge of –2mC, the new force of attraction will be
Two-point charges 2μC and 4μC are placed 2 cm apart. The ratio of the Coulomb’s force experienced by them is
(A) 1: 2
(B) 2: 1
(C) 1: 1
(D) 4: 1
Two charges of 2uC and 5uC are placed 2.5 cm apart. The ratio of Coulomb's force experienced by them is
Two charges q and –3q are placed on x-axis separated by distance d. Where a third charge 2q should be placed such that it will not experience any force ?
Derive an expression for electric field of a dipole at a point on the equatorial plane of the dipole. How does the field vary at large distances?
The potential energy of a charged parallel plate capacitor is \(U_0\). If a slab of dielectric constant K is inserted between the plates, then new potential energy will be
(a) \(U_0\)/K
(b) \(U_0\)K²
(c) \(U_0\)/K²
(d) \(U_0\)²
A Solid conducting sphere having a charge Q is surrounded by an uncharged concentric conducting spherical shell. Let the potential difference between the surface of the solid sphere and the outer of the shell be V. If the shell is given a charge -3Q the new potential difference between the same two surfaces is
1. 2V
2. V/2
3. V
4. -2V
Two sources of intensity I and 4I are used in an interference experiment . Find the intensity at points where waves from two sources superimpose with phase difference π/2 is
I. 4I
II. 6I
III. 5I
IV. 9I
Length of a hollow tube is 5 m, its outer diameter is 10 cm and thickness of its wall is 5 mm. If resistivity of the material of the tube is 1.7 x 10⁻⁸ Ωm, then the resistance of the tube will be
(a) 5.6 × 10⁻⁵ Ω
(b) 2 × 10⁻⁵ Ω
(c) 4 × 10⁻⁵ Ω
(d) None of these
In highly inductive load circuit, it is more dangerous when
(a) we close the switch
(b) open the switch
(c) increasing the resistance
(d) decreasing the resistance
Graph represents q verses V for two capacitors having same plate separation but different plate area . Which is the correct option
A parrot comes and sits on a bare high-power line. It will
A. experience a mild shock
B. experiences a strong shock
C. get killed instantaneously
D. not be affected at all