The magnetic force wire due the current wire

plane of the page

EK: 3.C.3 A magnetic force results from the interaction of a moving charged object or a magnet withother moving charged objects or another magnet. 2.D.1 The magnetic field exerts a force on a moving electrically charged object. That magnetic force is perpendicular to the direction of velocity of the object and to the magnetic field and is pro-portional to the magnitude of the charge, the magnitude of the velocity and the magnitude of the magnetic field. It also depends on the angle between the velocity, and the magnetic field vectors.

SP: 1.4 The student can use representations and models to analyze situations or solve problems qualitatively and quantitatively. 2.2 The student can apply mathematical routines to quantities that describe natural phenomena.

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(D) Alpha particle moving .1c, parallel to the magnetic field. (E) Beta particle moving .1c at a right angle to the magnetic field.

Answer: D=C < E < A=B

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AP2 Magnetism
A uniform magnetic field is directed into the plane of the page. A loop of wire is placed in the magnetic field. At no time does the loop leave the magnetic field. Which of the following situations will induce a current in the loop? Select two answers.

EK: 4.E.2 Changing magnetic flux induces an electric field that can establish an induced emf in a system.

SP: 1.4 The student can use representations and models to analyze situations or solve problems qualitatively and quantitatively. 6.4 The student can make claims and predictions about natural phenomena based on scientific theo-ries and models.

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(d) The flux through the loop doesn’t change, so the current in the wire remains the same.

EK: 2.D.1 The magnetic field exerts a force on a moving electrically charged object. That magnetic force is perpen-dicular to the direction of velocity of the object and to the magnetic field and is proportional to the magnitude of the charge, the magnitude of the velocity and the magnitude of the magnetic field. It also depends on the angle between the velocity, and the magnetic field vectors. 4.E.2 Changing magnetic flux induces an electric field that can establish an induced emf in a system.

AP2 Magnetism A magnetic field of strength B is oriented perpendicular to a rectangular loop of wire as shown. The width of the wire is w, and its length is L. The wire has a resistance per unit length of X ohms per meter. The wire is then uniformly rotated through an angle of θ about a vertical axis in a time period t. Assume θ is less than 90°.	L	B
	L	B

accuracy. Specifically highlight any additional equipment you would require.


	ΦBf −ΦBi	=LwB	(sinθ−1)
	t	t	(sinθ−1)
(c) I =ε R= LwB

LO: 4.E.2.1 The student is able to construct an explanation of the function of a simple electromagnetic device in which an induced emf is produced by a changing magnetic flux through an area defined by a current loop (i.e., a simple microphone or generator) or of the effect on behavior of a device in which an induced emf is produced by a constant magnetic field through a changing area. 4.E.4.2 The student is able to design a plan for the collection of data to determine the effect of changing the geometry and/or materials on the resistance or capacitance of a circuit element and relate results to the basic properties of resistors and capacitors.

		E	B
		E	B

greater than it was when the machine was functioning correctly.

(c) Which of the following are possible causes of this discrepancy? Justify your answers.

Answers: AP2 Magnetism (a) The electric force and the magnetic force must have matching magnitudes for the particle to pass through the velocity selector undeflected: Fe = FB → qE = qvB → v =E B

_No__ The magnetic field strength has increased.

Increasing the emf of the battery would allow more en-ergetic ions into the velocity selector, but only ions of the original velocity would exit the velocity selector.


(A) F/3 and to the right (B) F and to the left (C) 3F and to the left (D) F and to the right
		Wire 2

LO: 2.D.1.1 The student is able to apply mathematical routines to express the force exerted on a moving charged object by a magnetic field. 2.D.2.1 The student is able to create a verbal or visual representation of a magnetic field around a long straight wire or a pair of parallel wires.

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