# Magnetic Flux Formula

## Magnetic Flux Formula

The Magnetic Flux Formula is part of the Physics curriculum in multiple education boards in India. It is also a part of the Physics curriculum in multiple classes. The Magnetic Flux Formula can be learned with the help of the textbooks. The recommended textbooks are the most approachable learning materials to students. The textbook also contains multiple questions that can appear in the exams and tests. This makes textbook a go-to learning option for students. However, some questions in the textbooks might be challenging and confusing. This does not mean that students need to feel stuck with the solutions for these questions. Students can decide to learn from other sources to support their learning and exam preparation.

## Magnetic Flux Formula – Definitions & Practice Questions

It’s the component of the flux that passes through the coil that’s shared by all. Magnetic flux is represented by the symbol B, where B could be a field and therefore the unit is Weber (Wb). The magnetic flux value could be a vector quantity that depends on the flux direction.

Magnetic flux refers to the total number of magnetic field lines penetrating any surface placed perpendicular to the magnetic field. It is calculated as the product of the average magnetic field strength and the perpendicular area it penetrates.

Magnetic flux is denoted by ΦB where B represents magnetic field, and its unit is tesla-meter2 or weber (Wb).

Mathematically, the magnetic flux formula is as follows:

ΦB=B⃗ .A⃗ ΦB=B→.A→

Or,

ΦB=BAcosθ

Where, B is the magnetic field of force, A is the surface area or extent and θ is the angle between the normal to the surface and the magnetic field.

If a coil of n turns and area of cross section A is placed in a magnetic field of strength B, then the total flux associated with the coil is:

ΦB=nBAcosθ

Solved Examples

A magnetic field of 2.5 T passes perpendicular to a disc of radius 2 cm. Find the magnetic flux associated with the disc.

Solution: B = 2.5 T, r = 2 cm = 2 × 10–2 m, θ = 0,

ΦB=?ΦB=BAcosθ=2.5×π(2×10−2)2×cos0=3.14×10−3Wb

A coil of area of cross section 10–2 m2 and 100 turns is placed in a magnetic field of strength 1 T, with its axis making an angle 60° with the field. Find the total flux associated with the field.

Solution: B = 1 T, A = 10–2 m2,

θ=60∘,n=100,ΦB=?ΦB=nBAcosθ=100×1×10(−2)×cos60∘=0.5Wb

When the coil is rotated between the pole pieces of a magnet as shown, during one complete rotation of the coil, how often will the magnetic flux linked with the coil be maximum and minimum?

Options:

(a) maximum and minimum once each

(b) maximum and minimum twice each

(c) maximum once, minimum twice

(d) maximum twice, minimum once

Magnetic Properties of Electricity flowing through a Wire

There is no doubt that all of you have played with a magnet when you were a child. Iron or ferrous objects are attracted to this material because it attracts them. In addition to the metals, Chrome and Nickel are also two of the objects that are attracted to magnets. Eventually, when the characteristics of a magnet were discovered, a magnet was found to have two poles at both ends of its body when the characteristics of a magnet were found out. As the name implies, there are two poles—one is called the North Pole and the other is called the South Pole. It was later discovered that the electric current that passes through a metal wire possesses certain properties of magnetism, which have been discovered in later years of its existence. As a result, if the wire is turned into a spring or selenium and an electric current is passed through it, then the spring behaves like an actual magnet as it acts as if it were a coil of wire. A compass can be used to easily identify the north pole and south pole of this type of magnet by referring to its north and south poles.

A magnet or an electromagnet that has a magnetic force can be represented by a magnetic line that illustrates that force. The magnetic field lines of the magnets originate at the north pole of the magnets and end at the south pole of the magnets, completing a closed circuit through the magnet’s body and connecting the poles together. An iron object that comes in contact with a magnetic object will also behave as a magnet if it is brought close to the magnet. It is dependent on how many magnetic lines of force that originate from the actual magnet pass through this object in order to determine the quality of magnetic property of the magnet. As far as the quantity of magnetic force experienced by any object is concerned, the quantity of magnetic lines of force entering and exiting it can be measured. A term that is commonly used to describe the measurement of magnetic flux is Magnetic Flux Formula.

Practice Questions

Students can practise multiple questions on the Extramarks platform. The platform offers multiple learning options for students who do not want to rely solely on the textbooks for learning. This means that they will have extra learning support for examination preparations. Students can access the solved question papers to understand the Magnetic Flux Formula and its application. The topic of Magnetic Flux Formula has multiple aspect and comprehending all of them can be challenging. To fully understand the Magnetic Flux Formula, students should understand the textbook contents. However, relying solely on the textbooks is not enough in higher classes. Students need to learn from multiple sources to keep the learning going. The Magnetic Flux Formula along with other concepts can be learned with the help of the Extramarks platform. This platform allows students to acces all the important learning modules based on the Magnetic Flux Formula. This helps students build confidence while assisting them to prepare the Magnetic Flux Formula for examinations and tests.