NEET2016PhysicsElectromagnetic InductionActual
A uniform magnetic field is restricted within a region of radius, r . The magnetic field changes with time at a rate, d B → d t . Loop one of radius R > r encloses the region, r and loop two of radius, R is outside the region of magnetic field as shown in the figure below. Then the emf generated is
Options
- A0 in loop one and zero in loop two.
- B- d B → d t π r 2 in loop one and - d B → d t π r 2 in loop two.
- C- d B → d t π r 2 in loop one and infinite in loop two.
- D- d B → d t π r 2 in loop one and zero in loop two.
Correct answer
D. - d B → d t π r 2 in loop one and zero in loop two.
Step-by-step solution
Magnetic flux linked with area of loop one is B π r 2 . So, emf in loop one is, - d B → d t π r 2 . Magnetic flux linked with area of loop two is zero. So, emf in loop two is equal to zero.