Phys 259, Labatorial 8, Winter 2017 University of Calgary Department of Physics and Astronomy PHYS 259, Winter 2017 Labatorial 8: Magnetic Fields and Magnetic Force The figures above show two technical applications of magnetic fields: The image on the left shows the MRI scanner (General Electric, Waukesha, Wisconsin) at the Seaman Family MR Research Centre of the University of Calgary, located at Foothills Medical Centre. This machine is used for medical imaging research and generates a field strength of 3T. To put this in perspective, the average strength of the magnetic field of the Earth is about 50 microtesla. The image on the right shows the TRIUMF cyclotron, open for maintenance. The cyclotron was one of the earliest types of particle accelerators and was used as a source of high-energy beams for nuclear physics experiments for several decades. Today, cyclotrons still play a role in research as the first stage of multi-stage accelerators. In medical physics, they are used for isotope production for imaging and diagnostics. TRIUMF, Canada’s national laboratory for particle and nuclear physics is operated by a consortium of 15 Canadian University, including the University of Calgary, and is located on the UBC campus. It houses the world’s largest superconducting cyclotron, a source of 500 MeV protons. The magnet of the main cyclotron has a diameter of 18 m and produces a field of 0.46 T. Learning Goals: To understand the properties of magnetic fields, and how they are similar to or different from electric fields. To understand how a magnetic field affects the motion of charged particles, as compared to the effects of an electric field. Preparation: Halliday, Resnick, and Walker, “Fundamentals of Physics” 10th edition, Wiley: 28.1–28.5. Equipment: Slinky, table clamps, meter stick, ring stand with clamps, connecting wires, digital multimeter, DC power supply, Vernier magnetic field probe, Vernier LabPro Data Logger, Computer with Vernier Logger Pro. Note that there is an equation sheet at the end of this worksheet. 1
Phys 259, Labatorial 8, Winter 2017 1 From a single loop to a solenoid Question 1 : This figure shows a cut through a current-carrying loop, seen from the side. The current comes out of the page at the top and flows into the page at the bottom. At each point indicated by a solid dot, sketch and label a) the magnetic field vector generated by the top of the loop, b) the magnetic field vector generated by the bottom of the loop, and c) the net magnetic field generated by the loop. Question 2 : Just as in the case of electric fields, we can start from simple magnetic field configurations and construct more complicated fields using superposition. At each point indicated by a solid dot, sketch and label the magnetic field vectors for the field generated by the loop on the left, for the field generated by the loop on the right, and the net magnetic field vector.
- Summer '19
- Magnetic Field, power supply