What is the strength of transverse magnetic field required to bend all the photoelectrons within a circle of a radius 50 cm when light of wavelength 3800 mathringA is incident on a barium emitter? (Given that work function of barium is 2.5 eV; h=6.63× 10- 34 J s ; e=1.6× 10- 19 C ; m=9.1× 10- 31 kg )

Question

What is the strength of transverse magnetic field required to bend all the photoelectrons within a circle of a radius 50 cm when light of wavelength 3800 mathringA is incident on a barium emitter? (Given that work function of barium is 2.5 eV; h=6.63× 10- 34 J s ; e=1.6× 10- 19 C ; m=9.1× 10- 31 kg ) (A) 4.88× 10- 4T (B) 32× 10- 5T (C) 6.32× 10- 6T (D) 7.6× 10- 8T

Tardigrade Admin · Accepted Answer

(1/2) m v max 2=(h c/λ)-φ0 or v max 2=(2/m) (h c/λ)-Φ0 =(2/9.1 × 10-31) × (6.63 × 10-34 × 3 × 108/3.8 × 10-7)-2.5 × 1.6 × 10-19 =27.12 × 1010 m 2 s -2 NoW, B=(m v max /e R max )=(9.1 × 10-31 × 5.21 × 105/1.6 × 10-19 × 0.5) =6.32 × 10-6 T

$4.88 \times 1 0^{- 4} T$

$32 \times 1 0^{- 5} T$

$6.32 \times 1 0^{- 6} T$

$7.6 \times 1 0^{- 8} T$

Q. What is the strength of transverse magnetic field required to bend all the photoelectrons within a circle of a radius 50cm when light of wavelength 3800A˚ is incident on a barium emitter? (Given that work function of barium is 2.5eV;h=6.63×10−34Js ; e=1.6×10−19C ; m=9.1×10−31kg )

4.88×10−4T

32×10−5T

6.32×10−6T

7.6×10−8T

21​mvmax2​=λhc​−ϕ0​ or vmax2​=m2​λhc​−Φ0​ =9.1×10−312​×3.8×10−76.63×10−34×3×108​−2.5×1.6×10−19 =27.12×1010m2s−2 NoW, B=eRmax​mvmax​​=1.6×10−19×0.59.1×10−31×5.21×105​ =6.32×10−6T

$4.88 \times 1 0^{- 4} T$

$32 \times 1 0^{- 5} T$

$6.32 \times 1 0^{- 6} T$

$7.6 \times 1 0^{- 8} T$