1000 Solved Problems in Modern Physics

312 5 Solid State Physics

5.51 f=2eV/h→V=hf/^2 e
V=(6. 625 × 10 −^34 )(10^9 )/ 2 ×(1. 6 × 10 −^19 )
= 2. 07 × 10 −^6 V
= 2. 07 μV

5.52ΔB=

φ

A

=

(

1

5 , 000

)

φ 0 /π(3× 10 −^3 )^2

Substitutingφ 0 = 2. 0678 × 10 −^15 Tm^2 , we get

ΔB= 2. 93 × 10 −^14 T