BITSAT2011PhysicsElectromagnetic InductionActual
A metal rod of length 1 ~m is rotated about one of its ends in a plane right angles to a field of inductance 2.5 10⁻³ ~Wb / m ² . If it makes 1800 revolutions/min. Calculate induced e.m.f. between its ends.
Options
- A2.471 ~V
- B3.171 ~V
- C0.471 ~V
- D1.771 ~V
Correct answer
C. 0.471 ~V
Step-by-step solution
Given : =1 ~m , ~B =5 10⁻³ ~Wb / m ² f = 1800 60 =30 rotations / sec In one rotation, the moving rod of the metal traces a circle of radius r = Area swept in one rotation = r² array l d dt = d dt ( BA )= B d A dt = B r ² ~T = B f r ²= (5 10⁻³ ) 3.14 30 1=0.471 ~V array