Question
Question: At a place the value of horizontal component of the earth’s magnetic field H is 3 × 10<sup>–5</sup>w...
At a place the value of horizontal component of the earth’s magnetic field H is 3 × 10–5weber/m2. A metallic rod AB of length 2 m placed in east-west direction, having the end A towards east, falls vertically downwards with a constant velocity of 50 m/s. Which end of the rod becomes positively charged and what is the value of induced potential difference between the two ends
A
End A, 3 × 10–3Mv
B
End A, 3 Mv
C
End B, 3 × 10–3Mv
D
End B, 3 Mv
Answer
End A, 3 Mv
Explanation
Solution
According to Flemings right hand rule direction of induced current in rod AB is from B to A i.e. end A becomes positively charged. i.e. end A becomes positively charged.
emf induces across the ends of the rod
e = Hvl = 3 × 10–5 × 50 × 2 = 3 × 10–3 volt = 3mV.