Question and diagram below
The Attempt at a Solution
I really don't know how to start this question.
So to get the equation, would I have to start off with F=BIl and since Fnet=ma, ma=BIl and then incorporate time in it somehow, or would I have to start with ε=-NΔΦ/Δt?
Is this right?
You left out Δ in front of A. So a=(mgRΔt-(B^2)ΔAL)/ΔtmR wich equals(mgRΔt-ΔΦBL)/ΔtmR=a
Magnetic Flux is related to magnetic field by Flux=FieldxArea, and since the area of a rail gun would change as the bar moves down, ΔΦ=BΔA so that gives
Would this be right?
Wait, for (mgRΔt-(B^2)ΔAL)/ΔtmR=a , would that work? If the change in time is 0, then the acceleration is undefined.
Can you apply the kinematics equation into this since it is for constant acceleration?
The question says that the object falls from rest and with this solution, at t=0, a would =g and that would work since at t=0, the magnetic force would be 0 by F=qvb.