A soap bubble is charged to a potential 12V. If its radius is doubled,
A soap bubble is charged to a potential 12V. If its radius is doubled, then the potential of the bubble becomes
Options
(a) 12V (b) 24V (c) 3V (d) 6V
Correct Answer:
6V
Questions
A parallel plate capacitor as a uniform electric field E in the space between the plates
A parallel plate capacitor as a uniform electric field E in the space between the plates. If the distance between the plates is d and area of each plate is A, the energy stored in […]
Two metallic spheres of radii 1 cm and 3 cm are given charges of -1 x 10⁻² C
Two metallic spheres of radii 1 cm and 3 cm are given charges of -1 x 10⁻² C and 5 x 10⁻² C, respectively. If these are connected by a conducting wire, the final charge […]
The concentric spheres of radii R and r have positive charges q₁ and q₂ with equal
The concentric spheres of radii R and r have positive charges q₁ and q₂ with equal surface charge densities. What is the electric potential at their common centre?
Options
(a) σ/ε₀(R+r) (b) σ/ε₀(R-r) […]
A rod lies along the X-axis with one end at the origin and the other at x→∞. It carries
A rod lies along the X-axis with one end at the origin and the other at x→∞. It carries a uniform charge λCm⁻¹. The electric field at the point x=-a on the axis will be […]
The potential energy of particle in a force field is U = A/r² – b/r, where A and B
The potential energy of particle in a force field is U = A/r² – b/r, where A and B are positive constants and r is the distance of particle from the centre of the field. […]
Two metal spheres of radii 0.01m and 0.02m are given a charge of 15mC and 45mC
Two metal spheres of radii 0.01m and 0.02m are given a charge of 15mC and 45mC, respectively. They are then connected by a wire. The final charge on the first sphere is……x10⁻³C.
Options
If a mass of 20g having charge 3.0 mC moving with velocity 20ms⁻¹ enters a region
If a mass of 20g having charge 3.0 mC moving with velocity 20ms⁻¹ enters a region of electric field of 80NC⁻¹ in the same direction as the velocity of mass then the velocity of mass […]
An electric dipole of moment ‘p’ is placed in an elecatric field of intensity ‘E’
An electric dipole of moment ‘p’ is placed in an electric field of intensity ‘E’. The dipole acquires a position such that the axis of the dipole makes an angle θ with the direction of […]
If two charges +4e and +e are at a distance x apart, then at what distance charge q
If two charges +4e and +e are at a distance x apart, then at what distance charge q must be placed from +e, so that it is in equilibrium?
Options
(a) x/2 (b) x/3 […]