# Homework Help: Magnetic flux- is this the correct way to solve it?

1. May 8, 2017

### t123123

1. The problem statement, all variables and given/known data
As shown below, a rectangular wire loop of height 1.0 m, width 1.5 m, mass 0.10 kg, and resistance 10.0 Ω is pulled into a region of uniform magnetic field with magnitude 1.0 T pointing into the page (perpendicular to the plane of the loop). Determine the force necessary to pull the loop completely into the magnetic field region at a constant velocity of 5.0 m/s.

2. Relevant equations
magnetic flux=BA
inducedvoltage(V) =magnetic flux/dt
V=IR
F=qvB
3. The attempt at a solution
If magnetic flux is Z then
Z=BA
and V= Z/t = BA/ t
V=IR

IR=BA/t
Q/t *R =BA/t
then Q=BA/R
Q=1.0*(1.0*1.5)/10=.15C

F=.15C*5m/s*1.0T=0.75N

2. May 9, 2017

### cnh1995

What is the emf induced in the loop when the wire is moving with a velocity of 5m/s? Use the motional emf equation.
What is the current through the loop?

Finally, what is the force acting on the wire due to this current?

3. May 10, 2017

### t123123

Thank you! I think I figured it out.I needed to use F=ILB then F=V/RLB and F=dZ/dt/R*LB =BLv/R*LB which is L^2B^2V/R

4. May 12, 2017

### rude man

Looking good if you used L = side perpendicular to B and dZ/dt.