The direction of the magnetic force on a relocating positively charged particle or a wire delivering current $i$ in a unicreate magnetic fieldis established by the right-hand also rules through different versions proclaimed listed below.
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Version 1 (right-hand also rule): suggest the fingers of your best hand also in the direction of $vec v$ and also curl them (through the smaller sized angle) toward $vec B$. Your upideal thumb reflects the cross product $vec v imes vec B$ or the magnetic pressure $vec F_B$. This force is perpendicular to the aircraft of $vec v-vec B$
Version 2 (right-hand rule): suggest your fingers in the direction of $vec B$ so that the thumb points toward the velocity $vec v$, your palm mirrors the direction of the magnetic pressure on a positive charge.
Note: the magnetic force on an unfavorable charge is in opposite direction to that provided by the right-hand preeminence.
Right-Hand also Rule: Example problems
Example (1): What is the direction of the magnetic area that produces the magnetic force on a positive charge in each of the numbers listed below. (assuming $B$ is perpendicular to $v$).
Solution: right-hand also preeminence states that, to recognize the direction of the magnetic pressure on a positively charged ppost, allude the thumb of the righthand in the direction of $v$, the fingers in the direction of $B$, and also your palm in the direction of magnetic force $F$. Therefore, in the complying with figure we have
Where $odot$ and $otimes$ present the direction of the fieldsas exterior and also inward, respectively, perpendicular to the page.
Example (2): What is the direction of the magnetic force on a negative charge entering a unicreate magnetic area B in the complying with figure.
Solution: put your best fingers together with the velocity such that your palm reflects the direction of the magnetic field B. In this instance, your thumb, the direction of the magnetic force, goes into the page.
But note that this pressure is for a positive charge. For a negatively chargedparticle, simply reverse the above direction that is out of the web page.
Example (3): Using the right-hand also preeminence, find the direction of the magnetic pressure on the positively charged particle in the number listed below.
Solution: location your appropriate hand also on the airplane, such that your fingers directed in addition to the velocity V and also the palm to the magnetic area. Your thumb shows the direction of the magnetic pressure on the positive charge. This is the right-hand dominion.
In this difficulty, the thumb is towards the appropriate.
Example (4): Repeat the difficulty over with an unfavorable charge.
Solution: As a ascendancy of thumb, to discover the direction of the magnetic pressure on a negatively charged particle, first always mean the charge is positive, discover the force's direction on it then reverse its direction to uncover the force's direction on the corresponding negative charge.
Hence, in this trouble, the force is directed towards the left.
Example (5): Using the right-hand dominion, uncover the direction of the velocity in the adhering to number.
Solution: Respeak to that in the right-hand dominion, each component of the right hand also represents somepoint.
The fingers show the direction of the particle's velocityThe thumb is for the direction of the magnetic force.The palm mirrors the direction of the magnetic field.
Put your ideal hand also on the web page in the order described above. By doing this, your palm is facing up. Hence, the particle's velocity is out of the web page.
Example (6): An steady current passes through the wires in addition to a lengthy solenoid and produces a unidevelop magnetic area parallel to its axis. A positive charge relocating alengthy the axis of the solenoid enters right into it. In what direction is the magnetic force applied to the charge?
Solution: Recontact that the magnetic force on a charged particle is obtained by $F=qvecv imes vecB=qvBsin heta$ where $ heta$ is the angle between the particle's velocity and also the magnetic field.
Here, this angle is zero bereason both the velocity and also magnetic field are in the exact same direction.
Hence, no magnetic pressure is applied to the pwrite-up.
Example (7): a negatively charged pshort article, relocating to the right alengthy a horizontal airplane, is entering into an area of unicreate magnetic area directed right into the page. In what direction is the magnetic force?
Solution: First, visualize what is being said in the adhering to number.
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Now apply the right-hand also rule: your appropriate fingers together with the velocity so that the palm is in the direction of the magnetic area. The thumb, which suggests the force's direction, is upward.