Electro Magnetic Induction And Alternating Currents Question 467
Question: A conducting rod of mass m and $ \ell $ is placed on a smooth horizontal surface in a region where transverse uniform magnetic field B exists in the region. At t=0, constant force .F starts acting on the rod at its mid-point as shown. Potential difference between ends of the rod, $ V_{p}-V_{Q} $ at any time t is
Options:
A) $ \frac{BF\ell t}{2m} $
B) $ \frac{BF\ell t}{4m} $
C) $ \frac{5BF\ell t}{8m} $
D) $ \frac{7BF\ell t}{8m} $
Show Answer
Answer:
Correct Answer: A
Solution:
-
Velocity at any time t,
$ v=a $
$ t=\frac{F}{m}t $
Now, $ e=V_{P}-V_{Q}=Bv\ell ,\sin ,30^{o}=B( \frac{Ft}{m} )\ell \times \frac{1}{2} $
$ =\frac{BF\ell t}{2m} $
