AP EAMCET202021 Sep 2020Evening ShiftPhysicsMagnetic Effects of CurrentActual
When a helium nucleus covers a circle of radius (0.8 ~m ) in (2 ~s ), find the value of magnetic field (B ) at the centre of the circle.
Options
- A( 10⁻¹⁹ ₀ ~T )
- B( ₀ 10⁻¹⁹ ~T )
- C(2 ₀ 10⁻¹⁹ ~T )
- D( 2 10⁻¹⁹ ₀ ~T )
Correct answer
B. ( ₀ 10⁻¹⁹ ~T )
Step-by-step solution
Charge on helium nucleus, (q=+2 e=2 1.6 10⁻¹⁹ C =3.2 10⁻¹⁹ C ) Radius of helium nucleus, (r=0.8 ~m ) Time period, (T=2 ~s ) ( ) Current associated with helium nucleus, (I= q T = 3.2 10⁻¹⁹ 2 =1.6 10⁻¹⁹ ~A ) ( ) Magnetic field at the centre of the loop, (B= ₀ I 2 r = ₀ 1.6 10⁻¹⁹ 2 0.8 = ₀ 10⁻¹⁹ ~T )