## anonymous one year ago a 1.2 m long steel rod moves through a uniform magnetic field of 0.020 T at 20 m/s. What emf is induced between the two ends of the steel rod? A. 0.60 V B. 0.48 V C. 0.36 V D. 0.50 V *will draw inside!

1. anonymous

|dw:1434439190034:dw|

2. anonymous

the inner circles are shaded darker :)

3. Michele_Laino

inside our rod the Lorentz force is acting on the free electrons: |dw:1434439163697:dw|

4. anonymous

ok!

5. Michele_Laino

at the equilibrium thos forces, the lorentz force and the electrostatic force have the same magnitude, so we can write: $\Large eE = evB$ and then: $\Large V = vBL$ being L the length of the rod, and V the emf

6. anonymous

ok! what do we plug in? :/

7. Michele_Laino

$V = vBL = 20 \times 0.02 \times 1.2 = ...volts$

8. anonymous

we get 0.48! so choice B is the solutoin?

9. Michele_Laino

yes! that's right!

10. anonymous

yay!thanks!! okay, last one!!:)

11. Michele_Laino

ok! :)