The wavelength of photons in two cases are 4000 A ∘ and 3600 A ∘ , respectively, what is difference in stopping potential for these two?

According to Einstein's equation of photoelectric effect: h c λ = ϕ o + e V o . For case 1 : λ = 4 × 10 - 7 m h c 4 × 10 - 7 = ϕ o + e V o 1 . . . 1 For case 2 : λ = 3 . 6 × 10 - 7 m h c 3 . 6 × 10 - 7 = ϕ o + e V o 2 . . . 2 From the equation 1 and 2 , we get, e V o 2 - V o 1 = h c 3 . 6 × 10 - 7 - h c 4 × 10 - 7 ⇒ V o 2 - V o 1 = 6 . 62 × 10 - 34 × 3 × 10 8 1 . 6 × 10 - 19 1 3 . 6 × 10 - 7 - 1 4 × 10 - 7 ⇒ V o 2 - V o 1 = 0 . 34 volt .

The wavelength of photons in two cases are 4000 A ∘ and 3600 A ∘ , respectively, what is difference in stopping potential for these two?

According to Einstein's equation of photoelectric effect: h c λ = ϕ o + e V o . For case 1 : λ = 4 × 10 - 7 m h c 4 × 10 - 7 = ϕ o + e V o 1 . . . 1 For case 2 : λ = 3 . 6 × 10 - 7 m h c 3 . 6 × 10 - 7 = ϕ o + e V o 2 . . . 2 From the equation 1 and 2 , we get, e V o 2 - V o 1 = h c 3 . 6 × 10 - 7 - h c 4 × 10 - 7 ⇒ V o 2 - V o 1 = 6 . 62 × 10 - 34 × 3 × 10 8 1 . 6 × 10 - 19 1 3 . 6 × 10 - 7 - 1 4 × 10 - 7 ⇒ V o 2 - V o 1 = 0 . 34 volt .

The kinetic energy of the fastest moving photoelectron from a metal of work function 2 . 8 eV is 2 eV . If the frequency of light is doubled, then find the maximum kinetic energy of the photoelectron.

Given, work function ϕ o = 2 . 8 eV , Kinetic energy K E = 2 eV From Einstein photoelectric equation: h ν = ϕ o + K E ⇒ h ν = 2 . 8 + 2 eV = 4 . 8 eV . . . 1 If the incident frequency is doubled 2 ν . Hence, work function remains same ϕ o = 2 . 8 eV , 2 h ν = 2 . 8 eV + K E ⇒ 2 4 . 8 eV = 2 . 8 eV + K E From equation 1 ⇒ K E = 6 . 8 eV .

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The wavelength of photons in two cases are $4000 \overset{\circ}{A}$ and $3600 \overset{\circ}{A}$ , respectively, what is difference in stopping potential for these two?

Important Questions on Dual Nature of Matter and Radiation

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 4

The threshold frequency of a surface is

ν_{0}

. It is illuminated by

3 ν_{0}

frequency, the maximum speed of photoelectrons is

v m \sec^{- 1}

. What will be the maximum speed if the incident frequency is

9 ν_{0}

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 5

When the incident wavelength is

λ

, stopping potential is

3 V_{0}

. If the incident wavelength is

2 λ

, then stopping potential is

V_{0}

. Find out threshold wavelength in terms of

λ

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 6

A light beam of power

1.5 mW

and

400 nm

wavelength incident on a cathode. If quantum efficiency is

0.1 %

then, find out obtained photocurrent and number of photoelectrons per second.

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 7

A metallic surface of the work function

h ν

is illuminated by a radiation beam of frequency

5 ν

. The stopping potential observed is

X

. What will be stopping potential if the surface is illuminated by radiation of

7 ν

frequency?

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 8

The kinetic energy of the fastest moving photoelectron from a metal of work function

2.8 eV

2 eV

. If the frequency of light is doubled, then find the maximum kinetic energy of the photoelectron.

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 9

A monochromatic light incident on the metal

A

having threshold frequency

ν_{0}

. It emits photoelectrons of maximum kinetic energy

K

. Now the incident frequency is made three times and falls on a metal

B

having threshold frequency

2 ν_{0}

. What will the maximum kinetic energy of photoelectrons be emitted by metal

B

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 10

If the light of wavelength

4000 \overset{\circ}{A}

falls on a metal that has a stopping potential

1.4 volt

against photoelectric emission, then what is the work function of the metal. [Take

h = 6.6 \times 10^{- 34} J s

and

c = 3 \times 10^{8} m s^{- 1}

]

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Beta Question Bank for Medical: Physics>Chapter 32 - Dual Nature of Matter and Radiation>BEGINNER'S BOX - 2>Q 11

X-rays are produced in a X-ray tube by electrons accelerated through an electric potential difference of 50.0 kV. An electron makes three collisions in the target before coming to rest and loses half of its remaining kinetic energy in each of the first two collisions. Determine the wavelength of the resulting photons. (Neglect the recoil of the heavy target atoms)

The wavelength of photons in two cases are 4000 A∘ and 3600 A∘, respectively, what is difference in stopping potential for these two?

Important Questions on Dual Nature of Matter and Radiation

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The wavelength of photons in two cases are $4000 \overset{\circ}{A}$ and $3600 \overset{\circ}{A}$ , respectively, what is difference in stopping potential for these two?