KCET2019PhysicsMagnetic Effects of Current
A toroid has ( 500 ) turns per metre length. If it carries a current of ( 2 ~A ), the magnetic energy density inside the toroid is
Options
- A( 6.28 ~J / m 3 )
- B( 0.628 ~J / m 3 )
- C( 3.14 ~J / m 3 )
- D( 0.314 ~J / m 3 )
Correct answer
B. ( 0.628 ~J / m 3 )
Step-by-step solution
(B)Sol. Magnetic field inside a toroid [ B = _ o nl ] Magnetic energy density inside the toroid is [ array l u_ o = B² 2 _ o = _ o ² n² I² 2 _ o = _ o n² I² 2 = 4 10⁻⁷ (500)² 2² 2 =0.628 ~J ~m ⁻³ array ]