Phys 202 1nd Edition Lecture 13Outline of Last Lecture I. MagnetismOutline of Current Lecture II. Recap on Magnetic FieldIII. Definition of B FieldIV. Current and ChargeV. CyclotronsCurrent LectureRecap on Magnetic Field:The total magnetic flux through any closed surface, or in other words, the sum of flux through all the tinyareas in a surface, is equal to zero. Therefore, there is no such thing as a monopole. Definition of B field(magnetic field):If a charged particle were moving with a velocity (V), subject to a magnetic field (B), bearing a charge (Q),then this charge will experience a magnetic Force (FB). If the angle between the magnetic field and velocity is θ, then FB=|q||V||B|sin(θ).Remember that the magnetic force (FB) is perpendicular to the velocity (V) vector and the B field. The fact that the force is perpendicular to V means that the B field does no work. We know this because work is equal to the change in force times the change in movement. Since movement is along the x axis, B does no work.Current and charge:Remember that current (I) is equal to the change in charge over the change in time(ΔQ/Δt). If ΔQ is moving with a velocity (V);FB=ΔQ(l/Δt)BIn the case of the motion of a charged particle (Q) in a uniform B field, the velocity (V) remains the same.Therefore;FB=qVB(Sin(90))=mv2/rThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.qB=mv/r => V=qBr/mCyclotron:A cyclotron is a type of particle accelerator invented by Ernest Lawrence that accelerates a charged particle beam using a high frequency alternating voltage. This voltage is applied between two hollow "D"-shaped electrodes within a vacuum chamber. A narrow gap exists between the electrodes, creating acylindrical space for particles to move in between them. These particles are placed in the center of the space. A large electromagnet applies a magnetic field (B) perpendicular to the electrode plane. This magnetic field causes the path of the particles to form a circle due to the force perpendicular to their direction of motion.The period(T) is the time that it takes for the particle to complete one circle around the path;T=2πr/v => 2πrm/qBr =>
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