The Photon Model
Trending Questions
Photons of energy 6 eV are incident on a metal surface whose work function is 4 eV. The minimum kinetic energy of the emitted photo-electrons will be
Two identical capacitors each of capacitance are charged to potential and respectively. There negative ends are connected together, when the positive ends are also connected together, the loss of the energy of the system is.
- 1 : 2
- 2 : 1
- 1 : 4
- 4 : 1
- 2.0 V
- 0.8 V
- 4.0 V
- None of these
A tube light of 40 W runs at 220 V. What is the current in the tube light and how much energy in kWh it will consume in 10 hours?
- 1.4 eV
- 6.8 eV
- 5.4 eV
- 1.7 eV
If threshold wavelength for sodium is 6800∘A then the work function will be
1.8 eV
2.1 eV
2.5 eV
1.4 eV
The work function of a metal is 4.2 eV, its threshold wavelength will be
4000 ∘A
2500 ∘A
3500 ∘A
2955 ∘A
Define the threshold wavelength in the photoelectric effect.
- λ
- 3λ
- 4λ
- 2λ
The cathode of a photoelectric cell is changed such that the work function changes from W1 to W2 (W2>W1). If the current before and after change are l1 and l2 all other conditions remaining unchanged, then (assuming hn > W2)
I1=I2
I1>I2
I1<I2<2I1
I1<I2
Energy of photon whose frequency is 1012MHz, will be
4.14×102eV
4.14×103MeV
4.14×103KeV
4.14×103eV
- – 4.2 V
- – 9.4 V
- – 17.8 V
- +9.4 V
In the formula, , is ___ and is ___.
![](https://search-static.byjusweb.com/question-images/byjus/infinitestudent-images/ckeditor_assets/pictures/16023/content_1.png)
- 0.436×1018Hz
- 0.775×1015Hz
- 0.421×1025Hz
- 0.821×1023Hz
- 12.75
- 0.85
- 6.75
- 14.45
- Momentum of A is less than momentum of B.
- Wavelength of A is less than wavelength of B.
- Wavelength of A is equal to wavelength of B.
- Wavelength of A is greater than wavelength of B.
- Lithium
- Copper
- None of them can be used
- Both
If the work function of a metal is ′ϕ′ and the frequency of the incident light is 'v', there is no emission of photoelectron if
v<ϕh
v=ϕh
v>ϕh
v>=<ϕh
The photo-electrons emitted from a surface of sodium metal are such that
They all are of the same frequency
They have the same kinetic energy
They have the same de Broglie wavelength
They have their speeds varying from zero to a certain maximum
Mercury violet light (λ=4558 ∘A) is falling on a photosensitive material (ϕ=2.5 eV). The speed of the ejected electrons is in ms−1, about
3×105
3.65×107
2.65×105
4×104
Light of frequency 4v0 is incident on the metal of the threshold frequency v0. The maximum kinetic energy of the emitted photoelectrons is
3 hv0
2 hv0
32hv0
12hv0
The energy in monochromatic X-rays of wavelength 1 angstrom is roughly equal to
2×10−15 J
2×10−16 J
2×10−17 J
2×1018 J
When wavelength of incident photon is decreased then
Velocity of emitted photo-electron decreases
Photo electric current increases
Velocity of emitted photoelectron increases
Velocity of photoelectron do not charge
A hydrogen atom moving at a speed v absorbs a photon of wavelength 122 nm and stops. Find the value of v. Mass of a hydrogen atom =1.67×10−27 kg.
3.25 m/s
5.48 m/s
9.8 m/s
0.16 m/s.
The threshold wavelength for photoelectric effect of a metal is 6500 ∘A. The work function of the metal is approximately
2 eV
1 eV
3 eV
0.1eV
- 1 : 2
- 2 : 1
- 4 : 1
- 1 : 4
If the work function of a photometal is 6.825 eV. Its threshold wavelength will be (c=3×108 m/s)
1200 ∘A
1800 ∘A
2400 ∘A
3600 ∘A
Photons with energy are incident on a cathode in a photoelectric cell. The maximum energy of emitted photoelectrons is . When photons of energy are incident on , no photoelectrons will reach the anode , if the stopping potential of relative to is:
- 6.623×10−28
- 3×6.62×10−28
- 6.62×10−48
- 6.62×10−20