In fact, in a real wire only the negatively charged electrons move, as the positively charged protons remain bound to the atoms, which are stationary with respect to the body of the wire. The thumb points in the third orthogonal direction, namely in the direction of the magnetic force $F$ acting on the charge moving in magnetic right hand grip rule field. P1 and P2 are the positions of the magnetic compass, before and after passing a current through XY respectively.
As shown in the illustration, when looking from the end marked with “N”, the current appears to flow in the anticlockwise direction. At the same time, when looking from the end marked with “S”, the current appears to flow clockwise. Calculations of magnetic forces in three-dimensional space involve vector calculus, which by convention operates in a right-handed system, therefore right-hand rules (as outlined above) should be used accordingly. At a fundamental level it is not possible to calculate, in an absolute way, a value for binary quantities such as positive/negative (electric charge), clockwise/anticlockwise (direction of rotation), up/down (side of a surface), etc. They can only be defined with relation to each other, or to some closely related direction in the same system of coordinates.
- To determine the sense of rotation that such a torque vector would correspond to, about the axis defined by the torque vector itself, we use The Right Hand Rule For Something Curly Something Straight.
- Understanding the concept of right-hand grip rule is difficult for many students and so they commit silly mistakes in the examinations like using the left hand for the right-hand grip rule.
- However, nowadays there are publications which refer to the Fleming’s left-hand rule for magnetic force in motors and right-hand rule for generators.27)28)29)
- Electromagnetic waves consist of electric and magnetic fields oscillating perpendicular to each other, and their direction of propagation is determined by the magnetism right hand rule.
- The direction of flux lines of magnetic field, motion of the conductor and induced EMF and current can be found by Fleming’s left hand and right hand rules which we have discussed in the previous post.
- The magnetism right hand rule plays a vital role in the design and operation of electromagnetic coils in speakers and headphones.
The “hand rules” for directions of magnetic force were proposed in 1890 by John Ambrose Fleming.10)11) All these rules are equivalent, because the direction of the physical magnetic force (Lorentz force) is always the same. From the diagram it is clear that the moment arm r is just the magnitude of the component ┴ vector, in the perpendicular-to-the-force direction, of the position vector of the point of application of the force.
Class 10
As explained above, all these different versions (right or left hand, open palm or outstretched fingers) are exactly equivalent as far as the directions are concerned, because magnetic force always acts in the same way.34)35)36)37) In motors, the conventional movement of charges is caused by the conventional current which flows along the conductor in question. The magnetic force will push the conductor in the third orthogonal direction, causing physical movement of the conductor and generation of useful output torque. The middle finger shows the direction of the second vector, which is the direction of magnetic field $B$.
Solenoids
However, in generators, the charges are originally moved because the wire is pushed by some input torque. The charges move together with the wire, and the magnetic force pushes them along the wire, thus creating an electromotive force (EMF). It should be noted here that the magnetic force for a positive charge always follows this rule, regardless of any other conditions. Therefore, exactly the same right-hand rule is applicable to both motors and generators. For such loop, the magnetic poles N and S appear at each end, and they can be distinguished by the stylised letters with arrows at their ends, which show the apparent direction of “rotation” of current in the loop.
Right Hand Grip/Thumb Rule, Corkscrew Rule & End/Clock Rule
In some literature this rule is discussed as if it was a separate rule from the one described in the section above, but it results from the same principles. The right hand is depicted with the thumb following the direction of the current in a straight wire, and curled fingers show the direction in which the magnetic field (flux density B or magnetic field strength H) circulating around the wire.19) In simple words, a current carrying conductor creates a magnetic field around it. The lines of magnetic flux are in the shape of concentric circles and perpendicular on the conductor (at right angle of 90o) as shown in fig. The direction of current and magnetic field can be found by the following rules i.e. right hand gripping rule, the end rule, corkscrew rule, Fleming’s left and right hand rules etc.
Fleming’s Left & Right Hand Rules
Unlike most mathematical concepts, the meaning of a right-handed coordinate system cannot be expressed in terms of any mathematical axioms. Rather, the definition depends on chiral phenomena in the physical world, for example the culturally transmitted meaning of right and left hands, a majority human population with dominant right hand, or certain phenomena involving the weak force. A list of physical quantities whose directions are related by the right-hand rule is given below. (Some of these are related only indirectly to cross products, and use the second form.) For left-handed coordinates, the above description of the axes is the same, except using the left hand; and the ¼ turn is clockwise.
- The right hand rule is used to determine the direction of the magnetic field lines and current around a straight current carrying conductor, solenoid or coil inductor.
- The interaction between the current-carrying coil and the permanent magnet creates sound waves that produce the audio we hear.
- Now we add the line of action of the force and the moment arm r⊥ to the diagram, as well as the position vector r of the point of application of the force.
- Electromagnetic induction is the foundation of various electrical devices, including generators and transformers.
- A student needs to understand the topic and the elements of it in order to learn it.
The direction of flux lines of magnetic field, motion of the conductor and induced EMF and current can be found by Fleming’s left hand and right hand rules which we have discussed in the previous post. Beyond its applications in everyday devices, the magnetism right hand rule also helps us comprehend electromagnetic waves, which play a central role in modern communication and technology. Electromagnetic waves consist of electric and magnetic fields oscillating perpendicular to each other, and their direction of propagation is determined by the magnetism right hand rule. Understanding the concept of right-hand grip rule is difficult for many students and so they commit silly mistakes in the examinations like using the left hand for the right-hand grip rule. It should be kept in mind that this rule should only be performed with the right hand. Apart from determining the relationship between current and magnetic field it also shows that moving charges can create magnetic fields.
Right Hand, Left Hand, Thumb Rule – Compared
When viewed at a position along the positive z-axis, the ¼ turn from the positive x- to the positive y-axis is counter-clockwise. The various right- and left-hand rules arise from the fact that the three axes of three-dimensional space have two possible orientations. This can be seen by holding your hands together with palms up and fingers curled. If the curl of the fingers represents a movement from the first or x-axis to the second or y-axis, then the third or z-axis can point along either right thumb or left thumb.
Applications of the Magnetism Right Hand Rule
A positive charge is moving upwards in a magnetic field directed towards the north. By Physics experts to help you in doubts & scoring excellent marks in Class 9 exams. If you find curling your fingers too confusing, you can try this method that uses your thumb, pointer finger, and middle finger all 90 degrees apart. The hardest part of right-hand rule is imagining the different axes and envisioning how they are perpendicular to each other.
This rule is used in two complementary applications of Amperes circuital law which are; when an electric current is passed through a solenoid, a magnetic field is created. The thumb points towards the magnetic field line when the fingers are curled up around the wire in the direction of the flow of current. The right-hand grip rule is used to determine the relationship between the current and the magnetic field based upon the rotational direction.
The right hand rule is used to determine the direction of the magnetic field lines and current around a straight current carrying conductor, solenoid or coil inductor. A Danish physicist Hans Christian Orsted in 1820 discovered the relation between electricity and magnetism which states that “when current flows in a straight conductor, a magnetic field is produced in it. The polarity and density of the magnetic field depends on the direction and amount of current flowing through the conductor”. One of the fascinating phenomena explained by the magnetism right hand rule is electromagnetic induction. This process occurs when a conductor moves through a magnetic field or when there is a change in the magnetic flux through a circuit. Electromagnetic induction is the foundation of various electrical devices, including generators and transformers.
The magnetism right hand rule plays a vital role in the design and operation of electromagnetic coils in speakers and headphones. The interaction between the current-carrying coil and the permanent magnet creates sound waves that produce the audio we hear. The hardest part of the right-hand rule is imagining the different axes and envisioning how they are perpendicular to each other. This is most likely because the same kind of orthogonality can be represented by various configurations of fingers, on either hand. Fingers can be outstretched orthogonally, or the palm can be flat (hence slap rule). If the electric charge has a negative value (e.g. electron) then the force acts in the opposite direction.
By applying this rule, one can quickly grasp the complex interactions between magnetic fields and electric currents. This logic is consistent with the application of the vector cross product, as explained above for the right-handed system of coordinates. To find whether the axis of rotation is positive or negative, curl your fingers in the direction of rotation and your thumb shows the direction of rotation, i.e. whether rotation is along the positive or negative x y or z direction.
Right hand rule can also be used for determination of the magnetic field orientation and direction MRI machines use powerful magnetic fields to visualize internal structures in the human body. Understanding the magnetism right hand rule is crucial for optimizing and directing these magnetic fields to obtain clear and accurate images.
From predicting magnetic fields to understanding electromagnetic waves, this rule plays a crucial role in various applications, ranging from everyday devices like electric motors and speakers to cutting-edge technologies like MRI machines and particle accelerators. In particle accelerators, charged particles experience magnetic forces as they move through magnetic fields. Scientists use the magnetism right hand rule to design and control the trajectories of these particles, enabling cutting-edge research in physics. Magnetic compasses are essential navigation tools, and they operate based on the magnetism right hand rule. The compass needle aligns itself with Earth’s magnetic field, indicating the North-South direction. However, nowadays there are publications which refer to the Fleming’s left-hand rule for magnetic force in motors and right-hand rule for generators.27)28)29)