Electric fields and charges practice · Medium

A particle of mass $\text{m}$ and charge $\text{q}$ travelling with a velocity $\text{v}$ along the X-axis enters a uniform electric field $\overrightarrow{\mathrm{E}}$ directed along the $\mathrm{Y}$-axis. What will be the trajectory of the particle?

A neutron, a proton and an electron are placed in a uniform electric field.

A positively charged ball hangs from a silk thread. We put positive test charge $q_0$ at a point and measure $F / q_0,$ then it can be predicted that the electric field strength ${E}$

A charge $Q$ is divided into two parts of $q$ and $Q - q$ If the coulomb repulsion between them when they are separated is to be maximum, the ratio of $\frac{Q}{q}$ should be

Assertion(A): In an uniform magnetic field,
speed and kinetic energy remains the same
for a moving charged particle.

Reason (R): In the case of motion of a charge
in a magnetic field, the magnetic force is
perpendicular to the velocity of the particle.
So, no work is done and no change in the
magnitude of the velocity (speed) and
kinetic energy is produced.

Electric charges are distributed in a small volume. The flux of the electric field through a splerical surface of radius $1 \mathrm{~m}$ surrounding the total charge is $100 \mathrm{~V}-\mathrm{m}$. The flux over the concentric sphere of radius $2 \mathrm{~m}$ will be:

An electron enters in an electric field with its velocity in the direction of the electric lines of force. Then

A particle of mass M and charge q is released from rest in a region of uniform electric field of magnitude E. After a time t, the distance travelled by the charge is S and the kinetic energy attained by the particle is T. Then, the ratio $\frac{T}{S}:$

Flux coming out from a unit positive charge enclosed in air is

For a uniformly charged ring of radius $R,$ the electric field on its axis has the largest magnitude at a distance $h$ from its centre. Then, value of $h$ is

Assertion: If an electron and proton possessing same kinetic energy an electric field in a perpendicular direction, the path of the electron is more curved than that of the proton

Reason: Electron forms a large curve due to its small mass

An infinite number of point charges of same magnitude are kept along $X$-axis at $x=1 \mathrm{~cm}, x$ $=2 \mathrm{~cm}, x=4 \mathrm{~cm}, x=8 \mathrm{~cm}, \ldots$ and so on. If the magnitude of charge is $5 \mathrm{~nC}$ and consecutive charges are of opposite sign, the magnitude of electric field at $x=0$ is

Van de Graaff electrostatic generator is based on:

A point charge q produces an electric field of magnitude $2\mathrm{ }N{C^{ - 1}}$ at a point distance 0.25 m from it. What is the value of charge?

Assertion: Electric lines of force never cross each other.
Reason: Electric field at a point superimpose to give one resultant electric field
In above question a statement of assertion is followed by statement of reason mark the correct choice.

The electrostatic field lines

A ring of radius $r$ carries a charge $Q$ uniformly distributed over its length. A charge $q$ is placed at its centre will experience a force equal to

There is 10 units of charge at the centre of a circle of radius $10m.$ The work done in moving 1 unit of charge around the circle once is

Which is the incorrect statement regarding
electric lines of force?

Two isolated metallic solid spheres of radii $R$ and $2 R$ are charged such that both have same charge density $\sigma$. The spheres are then connected by a thin conducting wire. If the new charge density of the bigger sphere is $\sigma^{\prime}$. The ratio $\frac{\sigma^{\prime}}{\sigma}$ is

Electric field due to point charge depends on distance $r$ as

What happens when some charge is placed on a soap bubble?

Assertion: Work done by electric force is path independent.

Reason: Electric force is conservative.

Which of the following statement is correct?

A charge $Q$ is uniformly distributed over a large square plate of copper. The electric field at a point very close to the centre of the plate is $10 \mathrm{~V} / \mathrm{m}$. If the copper plate is replaced by a plastic plate of the same geometrical dimensions and carrying the same charge Q uniformly distributed, then the electric field at the point $P$ will be :-

Find the ratio of the magnitude of the electric force to the gravitational force acting between two protons.

Assertion: Electrostatic forces are attractive as well as repulsive in nature.
Reason : Charges are positive and negative in nature.

In a region, the potential is represented by $V(x, y, z)=6 x-8 x y-8 y+6 y z,$ where $V$ is in volts and $x, y, z$ are in metres. The electric force experienced by a charge of $2 \mathrm{~C}$ situated at point $(1,1,1)$ is

If a conducting medium is placed between two
charges, then the electric force between them
will become

A free proton and a free electron are placed in a uniform electric field. Which of the following statements are correct?

A. The magnitudes of electric forces acting on them will be equal.

B. Their accelerations will be different.

C. They will move in the same direction.

Select the correct answer using the code given below.