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Chapter 21 Conceptual Questions 2,4, & 6. Suppose you accidentally use your left hand, instead of your right, to determine the direction of the magnetic force on a positive charge moving in a magnetic field. Do you get the correct answer? If not, what direction do you get?.
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Chapter 21 Conceptual Questions 2,4, & 6 Suppose you accidentally use your left hand, instead of your right, to determine the direction of the magnetic force on a positive charge moving in a magnetic field. Do you get the correct answer? If not, what direction do you get?
Chapter 21 Conceptual Questions 2,4, & 6 Suppose that the positive charge in Figure (a) were launched from the negative plate toward the positive plate, in a direction opposite to the electric field. A sufficiently strong electric field would prevent the charge from striking the positive plate. Suppose the negative charge in Figure (b) were launched from the south pole toward the north pole, in a direction opposite to the magnetic field. Would a sufficiently strong magnetic field prevent the charge from reaching the north pole? Account for your answer.
Chapter 21 Conceptual Questions 2,4, & 6 Review Conceptual Example 4 as background for this question. Three particles have identical charges and masses. They enter a constant magnetic field and follow the paths shown in the picture. Which particle is moving the fastest, and which is moving the slowest? Justify your answers.
Chapter 21 Conceptual Questions 2,4, & 6 • Suppose you accidentally use your left hand, instead of your right, to determine the direction of the magnetic force on a positive charge moving in a magnetic field. Do you get the correct answer? If not, what direction do you get? You do not get the correct answer, you would get the opposite direction.
Chapter 21 Conceptual Questions 2,4, & 6 Suppose that the positive charge in Figure (a) were launched from the negative plate toward the positive plate, in a direction opposite to the electric field. A sufficiently strong electric field would prevent the charge from striking the positive plate. Suppose the negative charge in Figure (b) were launched from the south pole toward the north pole, in a direction opposite to the magnetic field. Would a sufficiently strong magnetic field prevent the charge from reaching the north pole? Account for your answer. No. Because the charge is launched directly along the magnetic field lines, the angle between the charge’s velocity and the magnetic field is zero degrees. (v and B are parallel) Considering the equation relating force, velocity, and magnetic field strength: F = B∙v∙q∙sinθ If the angle between B and v is 0o or 180o, then sinθ = 0 and there is no magnetic force.
Chapter 21 Conceptual Questions 2,4, & 6 Review Conceptual Example 4 as background for this question. Three particles have identical charges and masses. They enter a constant magnetic field and follow the paths shown in the picture. Which particle is moving the fastest, and which is moving the slowest? Justify your answers. A tighter arc means greater acceleration. Since all particles are identical in mass, Newton’s 2nd Law (F = ma)tells us that the particle forming the tightest arc must be experiencing the most force. Consider the equation relating magnetic force to magnetic field strength, particle speed, and particle charge: F = B∙v∙q∙sinθ Solving for v, we have: v = F/B∙q∙sinθ We know that each particle has the same charge and enters the same magnetic field at presumably the same angle. Simplifying the equation above, we can see that the force F on a charged particle is dependent only on the particle’s velocity, v: v = F Since #1 has the largest arc, it must have been moving the slowest. Since #2 has the smallest arc, it must have been moving the fastest. #3 is in the middle.
