BlogNCERTForce on a Moving Charge in Uniform Magnetic and Electric Field

Force on a Moving Charge in Uniform Magnetic and Electric Field

The Lorentz force (or electromagnetic force) is indeed the outcome of electromagnetic fields combining electric and magnetic forces on a point charge. In an electric field E and a magnetic field B, a charge q particle travelling with a velocity v experiences a force of. The electromagnetic force on a charge q is described as a combination of a force in the direction of the electric field E, proportional to the magnitude of field and the quantity of charge, as well as a force at right angles to the magnetic field B and the charge’s velocity v, proportional to the magnitude of the field, the charge, and the velocity. The magnetic force on the current-carrying wire (often termed as the Laplace force), the electromotive force in a sterile loop travelling through a magnetic field, and also the force on a moving charged particle are all described by variations on this basic formula.

A brief outline

E and B are defined by the Lorentz force law.

The electromagnetic force F on a test charge at a given position and time is a function of its charge q and velocity v, that can be quantified in the functional form by exactly two vectors E and B:

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    F = q (E + v * B)

    Even for particles close to the speed of light (that is, the magnitude of v, |v| c), this holds true. As a result, the two vector fields E and B are defined in space and time, and they are referred to as the “electric field” and “magnetic field,” respectively. Irrespective of whether a charge is accessible to experience the force, the fields are specified everywhere in space and time in terms of what force a test charge might receive.

    Since a real particle (as distinguished to a hypothetical “test charge” with infinitesimally minuscule mass and charge) would create its own finite E and B fields, altering the electromagnetic force it experiences, the Lorentz force is just a theoretical definition.

    Important concepts

    What does a magnetic field causes in terms of force?

    Magnetic fields can only exert a force on a moving electric charge, as a moving charge generates a magnetic field. With a rise in charge and magnetic force strength, this force increases. Furthermore, when charges have higher velocities, the force is stronger.

    However, the magnetic force is always transverse to the velocity. As a result, this force could never produce stuff on the charge or transfer kinetic energy to it. The magnetic field is defined as

    Fm= q v × B

    Q = charge

    V = velocity

    B = Magnetic field

    It’s worth noting that the cross product implies that the force is always perpendicular to the velocity and magnetic field. As a result, it always acts outside of the plane and contributes nothing to the charge’s work. It can only modify the velocity’s direction; it can’t change the magnitude. Using Fleming’s Right-hand Rule, you may quickly calculate the force’s direction.

    Parallel to the electric fields axis If is 0, the particle has no magnetic force and will continue to flow along the field lines undeflected. When v and B are at right angles, charged particle accelerators like cyclotrons exploit the fact that particles move in a circular orbit. A perfectly timed electric field provides the particles greater kinetic energy with each round, causing them to move in increasingly bigger circles. When the particles once attained the necessary energy, they are collected and used in a variety of applications, ranging from subatomic particle research to cancer treatment.

    The symbol of the charge carriers in a conductor is disclosed by the magnetic force on a moving charge. Positive charge carriers going from right to leave, negative charge carriers moving from left side to right side, or some mix of the two can cause a current to flow from right to left in a conductor.

    What is the electric field’s force?

    The electric field’s force on a charge is integrated into its definition. It always functions in either parallel or anti-parallel to an electric field, regardless of the charge’s velocity. This indicates that it can work and provide energy to the charge.

    Fe = q E

    The magnetic force along both types of excitons is in the same direction when a conductor is put in a B field perpendicular to the current. This force causes a tiny potential difference between the conductor’s sides. When an electric field is coordinated with the direction of the magnetic force, this phenomenon is known as the Hall effect. The Hall effect demonstrates that electrons dominate copper’s conductance. Conduction in zinc, on the other hand, is dominated by the movement of positive charge transporters. When electrons in zinc are stimulated from the valence band, they leave holes, which act as positive charge carriers. The majority of the electrical conduction in zinc is due to the mobility of these holes.

    Significance of force on a moving charge in uniform magnetic and electric field in NEET exam

    NEET themes are designed to clarify and provide the most likely questions to be asked on the exam. Observations from competent scholars in the field, which are published on the Infinity Learn free website, can be used to explain them in simple words. If students have a thorough comprehension of the topics covered during the program, multiple-choice questions are easy to practice.

    The current page on Lorentz’s force covers all aspects of the force acting on a moving charge in uniform magnetic and electric fields. Examine the detailed notes attentively to ensure that you understand this topic, as it will improve your NEET exam preparation. One can also record some notes on elastic energy for further review.


    Lorentz’s force outlines the mathematical equations and also the physical significance of loads exerted on charged particles travelling through space with both electric and magnetic fields. This is why the Lorentz force is so important.

    The Lorentz force is used in the following ways:

    • Lorentz force is used in cyclotrons as well as other particle accelerators.
    • The Lorentz force is used in a bubble chamber to create the graph used to calculate the paths of charged particles.
    • The Lorentz force is used in cathode ray tube televisions to divert electrons in a straight line so that they land on precise areas on the screen.

    Also read: Important Topic of Physics: Superposition Principle

    FAQs (Frequently asked questions)

    Question 1: What is Lorentz force, and how does it work?

    Answer: Lorentz force refers to the force exerted on a charged particle by electric and magnetic fields.

    Question 2: What is the Lorentz force calculation formula?

    Answer: F=q (E +v B)

    Question 3: Who is the Lorentz force named after?

    Answer: Hendrik Lorentz is the name of the Lorentz force.

    Question 4: How many gauss does one tesla equal?

    Answer: A Tesla has a Gauss of 10,000.

    Question 5: To calculate the magnetic force, which law is being used?

    Answer: The Rule of Right-Handedness.

    Question 6: What are the characteristics of electric and magnetic forces in terms of fields?

    Answer: Magnetic forces have always been perpendicular to the field, but electric forces are always collinear.

    Question 7: What is Lorentz Force and How Does It Work?

    Answer: In the existence of both E and B fields, it is useful to detect the direction of travelling charge.

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