Velocity(t), of rod moving in B-field

Thread starter serverxeon
Start date Mar 12, 2013
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B-field Rod

AI Thread Summary

The discussion focuses on deriving the expression for the velocity of a rod moving in a magnetic field using energy approaches and Newton's second law. The user expresses difficulty in solving the differential equation for velocity, v(t). Another participant suggests that taking the derivative of the last equation could yield a differential equation for v(t), but notes that applying Newton's second law directly may be simpler. The conversation emphasizes the relationship between force, mass, and acceleration in this context. The participants are exploring methods to effectively solve the problem of the rod's motion in the magnetic field.

Mar 12, 2013

serverxeon

Here's the question

-------------------

Here's my attempt using energy approach.

However, I'm kinda stuck. how do I solve this DE to get the expression for v(t)?

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Mar 12, 2013

TSny

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I think it will be much simpler to just apply Newton's second law: ##F = ma = m\dot{v}##

[You could take the derivative with repsect to t of both sides of your last equation and get a differential equation for v(t), but it will be the same as just setting up F = ma.]

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