(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

a wire 0.3 meters in length is suspended in a region in which a uniform magnetic field of 4Teslas points into the page as shown ( see attach.). the wire is dropped at time t = 0 seconds. at what times will there be an electric potential of 98 volts between the ends of the wire? also, which end of the wire will have the higher potential?

2. Relevant equations

position x = 1/2(at^2) where a is acceleration due to gravity = 9.8m/s/s, t is time

force of gravity F = mg where m is mass, g is gravity = 9.8m/s/s

1/2(mv^2) = qV where q is charge, V is electric potential

magnetic force F_m = qv X B where q is charge, v is velocity, B is magnetic field, X indicates cross product

gravitational potential energy U = mgh where m is mass, g is gravity = 9.8 m/s/s, h is height = x

gravitational potential energy = kinetic energy = 1/2 (CV^2) = 1/2(mv^2) where C is capacitance, V is electric potential, m is mass, v is velocity

3. The attempt at a solution

i'm guessing most of the above equations are not needed at all.

i'm not too sure how to do this, but this is what i've been scheming: use the " 1/2(mv^2) = qV " to solve for v while holding m and q constant.

sub in v into magnetic force eq and solve for force, and since force F = ma = m ( 1/2(at^2)) where m is constant, and a = 9.8m/s/s i can solve for t.

is this close? i haven't included the given length of 0.3 meters, though.

as for the second 'part', determining which end of the wire has the higher potential i am not too sure about, tips appreciated.

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# Homework Help: Finite wire in magnetic field, determine time and electric potential

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