AP EAMCET202022 Sep 2020Morning ShiftPhysicsMagnetic Effects of CurrentActual
When a helium nucleus makes a full rotation of a circle of radius 0.8 ~m in 2.5 ~s , then the value of magnetic field B at the centre of the circle will be
Options
- A4 10⁻²⁵ ~T
- B2 10⁻²⁶ T
- C4 10⁻²⁶ ~T
- D2 10⁻²⁵ ~T
Correct answer
C. 4 10⁻²⁶ ~T
Step-by-step solution
Charge on helium nucleus, aligned q & =2 e=2 1.6 10⁻¹⁹ & =3.2 10⁻¹⁹ C r & =0.8 ~m , ~T =2.5 ~s aligned Current associated due to one rotation of helium nucleus, I= q T = 3.2 10⁻¹⁹ 2.5 =1.28 10⁻¹⁹ ~A Magnetic field at the centre of the circle formed by helium nucleus, aligned B & = ₀ I 2 r = 4 10⁻⁷ 1.28 10⁻¹⁹ 2 0.8 & =3.2 10⁻²⁶ ~T aligned which is nearest to 4 10⁻²⁶ ~T .