Electric fields and charges practice · Medium

If a point charge $\mathrm{q}$ is placed at the centre of a cube what is the flux linked with the cube?

Assertion: Electric and gravitational fields are acting along same line. When proton and $\alpha$-particle are projected up veritically along that line, the time of flights is less for proton.

Reason: In the given electric field acceleration of a charged particle is directly proportional to specific charge.

Charge on $\alpha$ particle is

$A,B,C$, are three points on a circle of radius $1\,\,cm$. These points from the corners of an equilateral triangle. A charge $2C$ is placed at the centre of the circle. The work done in carrying a charge of $0.1\,\mu C$ from $A$ to $B$ is

Statement-1: A uniformly charged dise has a pin hole at its centre. The electric field at the centre of the disc is zero.
Statement-2: Disc can be supposed to be made up of many rings. Also electric field at the centre of uniformly charged ring is zero.

Plastic rod rubbed with fur and glass rod rubbed with silk

Assertion: Vehicle carrying highly inflammable materials having hanging chains, slightly touching the ground.

Reason: The body of a vechicle gets charged when moving through air at high speed.

The distance between a proton and electron both having a charge $1.6 \times {10^{ - 19}}coulomb,$ , of a hydrogen atom is ${10^{ - 10}}metre.$. The value of intensity of electric field produced on electron due to proton will be

The dimensional formula of electric charge is:

One of the following is not a property of field lines

Two identical conductors of copper and aluminum are placed in an identical electric fields. The magnitude of induced charge in the aluminum will be

Mark the incorrect statement among the following.

Two charged particles of same specific charge (i.e. charge per unit mass) are projected in same uniform magnetic field with projection velocities, perpendicular to the magnetic field. If the speeds of charged particles are $v$ and $2 v$, then the ratio of angular speeds of the path of the particles in magnetic field will be

Assertion: A point charge is brought in an electric field. The field at a nearby point will increase, whatever be the nature of the charge.

Reason: The electric field is independent of the nature of charge.

Two particles of masses in the ratio $1: 2$, with charges in the ratio $1: 1$, are placed at rest in a uniform electric field. They are released and allowed to move for the same time. The ratio of their kinetic energies will be finally

If the electric flux entering and leaving an enclosed surface respectively are ${\phi _1}$ and ${\phi _2}$, the electric charge inside the surface will be

Assertion: Coulomb force between charges is central force.

Reason: Coulomb force depends on medium between charges.

The electric field in a certain region is given by $\vec{E}=5 \hat{i}-3 \hat{j} k V / m.$ The potential difference $V_B-V_A$ between points $A$ and $B,$ having coordinates $(4,0,3) \,\mathrm{m}$ and $(10,3,0) \,\mathrm{m}$ respectively, is equal to

A circular loop of radius a carries a total charge $Q$ distributed uniformly over its circumference. A small length ${dL}$ of the wire is cut off. The magnitude of electric field at the center due to remaining wire will be $\left[K=\frac{1}{4 \pi \varepsilon_0}\right]$

Assertion: Electrostatic field lines start at positive charges and end at negative charges.
Reason: Field lines are continuous curves without any breaks and they form closed loop.

Electrical force is acting between two charges kept in vacuum. A copper plate is placed between the charges, the force now is

Assertion: Induced charge does not contribute to electric field or potential at a given point.

Reason: A point chagre $q_0$ is kept outside a solid metallic sphere, the elcetric field inside the sphere is Zero.

Statement I: The electrostatic field lines cannot form a closed path

Statement II: The magnetic field lines form a continuous closed path

Consider a neutral conducting sphere. A positive point charge is placed outside the sphere. The net charge on the sphere is then

When a number of charged liquid drops coalesce, which of the following quantity does not change?

Assertion : Work done in moving a charge between any two points in an electric field is independent of the path followed by the charge, between these points.

Reason: Electrostatic force is a non conservative force.

The Gaussian surface for calculating the electric field due to a charge distribution is

Statement-I: Flux through a closed surface is zero

Statement-II: Total charge inside the surface must be zero

Consider the following two statements
a) Electric field is always conservative in nature.
b) In electromagnetic waves the phase difference between oscillating electric and magnetic field is ${90^\mathrm{o}}$
The corerct statement (s) is/are

An infinite number of charges, each of magnitude $\mathrm{q}$, are placed along $\mathrm{X}$-axis at $\mathrm{x}=1 \mathrm{~m}, 2 \mathrm{~m}, 4 \mathrm{~m}, 8 \mathrm{~m}, 16 \mathrm{~m}$ and so on but the consecutive charges are of opposite sign starting with $+\mathrm{q}$ at $\mathrm{x}=1 \mathrm{~m}$. A point charge $\mathrm{q}_0$, kept at the origin, experiences a force of magnitude: