Download MC1:The diagram shows a positively charged particle is moving with

MC1:The diagram shows a positively charged particle is moving with velocity v in a magnetic field B directed out of
the page. Using the right diagram, the direction of the magnetic force on the particle is
A) 1 B) 2 C) 3 D) 4 E) 5
MC2: A proton with a charge +e is moving with a speed v at 50º to the direction of a magnetic field . The component
of the resulting force on the proton in the direction of B is
A) evB sin 50º cos 50º
B) evB cos 50º
C) zero
D) evB sin 50º
E) None of these is correct.
MC3:A uniform magnetic field of 0.5 T is parallel to the z axis. A square coil of side 10 cm has 300 turns and lies in
the xy plane as shown. The magnetic flux through the coil is
A) 0.14 Wb B) 0.75 Wb C) 1.5 Wb D) 0.27 Wb E) zero
MC4:A loop rests in the xy plane. The z axis is normal to the plane and positive upward. The direction of the changing
flux is indicated by the arrow on the z axis. The diagram that correctly shows the direction of the resultant induced
current in the loop is
A) 1 B) 2 C) 3 D) 4 E) 5
MC5:The Nernst equation relates the potential difference across a membrane to the equilibrium ratio of
A) nernstons B) nucleic acid C) myelin D) ionic concentration E) axons
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Problem 1 :You have the following laboratory problem: you need to separate two isotopes of lithium using a mass
spectrometer. Lithium-6 (mass 1.00 ◊ 10≠26 kg) and Lithium-7 (mass 1.17 ◊ 10≠26 kg) are heated in an oven until
singly ionized (i.e. the atoms lose one electron) and the ions 6 Li+ and 7 Li+ are accelerated from rest through the same
potential difference V . The magnetic field of the spectrometer is 0.5 Tesla. (a) First, starting from the formula for
centripetal acceleration, ac = v 2 /r, derive an expression for the radius of a charged particle orbit inside the B-field
region. Show explicitly that your formula yields dimension of length. (b) What is the minimum value of the potential
difference through which these ions must be accelerated if the separation distance between them on the detector screen
must be 2.0 mm (assume the mass ratio is 7/6)? (c) if you increase the accelerating potential, will the separation
increase or decrease, and why?
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Problem 2 : The section of wire shown in the figure carries a current equal to 1.8 A from a to b. The segment is in
a region that has a magnetic field whose value is 1.2 T k̂ along the z axis. Find the total vector force F on the wire
and show that the total vector force is the same as if the wire were in the form of a straight wire directly from a to b
and carrying the same current.
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