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## Numerical

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A freshly prepared radioactive source of half life 2 hours 30 minutes emits radiation which is 64 times the permissible ...
JEE Main 2022 (Online) 28th July Morning Shift
Two lighter nuclei combine to form a comparatively heavier nucleus by the relation given below : $${ }_{1}^{2} X+{ }_{1}... JEE Main 2022 (Online) 26th July Evening Shift When light of frequency twice the threshold frequency is incident on the metal plate, the maximum velocity of emitted el... JEE Main 2022 (Online) 24th June Morning Shift The stopping potential for photoelectrons emitted from a surface illuminated by light of wavelength 6630$$\mathop A\lim...
JEE Main 2022 (Online) 26th June Evening Shift
The K$$\alpha$$ X-ray of molybdenum has wavelength 0.071 nm. If the energy of a molybdenum atoms with a K electron knock...
JEE Main 2021 (Online) 27th July Evening Shift
A transistor is connected in common emitter circuit configuration, the collector supply voltage is 10 V and the voltage ...
JEE Main 2021 (Online) 27th July Morning Shift
A radioactive sample has an average life of 30 ms and is decaying. A capacitor of capacitance 200 $$\mu$$F is first char...
JEE Main 2021 (Online) 27th July Morning Shift
A light beam of wavelength 500 nm is incident on a metal having work function of 1.25 eV, placed in a magnetic field of ...
JEE Main 2021 (Online) 25th July Evening Shift
A certain metallic surface is illuminated by monochromatic radiation of wavelength $$\lambda$$. The stopping potential f...
JEE Main 2021 (Online) 20th July Evening Shift
If 2.5 $$\times$$ 10$$-$$6 N average force is exerted by a light wave on a non-reflecting surface of 30 cm2 area during ...
JEE Main 2021 (Online) 17th March Morning Shift
Two stream of photons, possessing energies equal to twice and ten times the work function of metal are incident on the m...
JEE Main 2021 (Online) 26th February Evening Shift
The surface of a metal is illuminated alternately with photons of energies E1 = 4 eV and E2 = 2.5 eV respectively. The r...
JEE Main 2020 (Online) 5th September Evening Slot
A beam of electromagnetic radiation of intensity 6.4 × 10–5 W/cm2 is comprised of wavelength, $$\lambda$$ = 310 nm. It ...
JEE Main 2020 (Online) 7th January Morning Slot

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The half life period of a radioactive substance is 60 days. The time taken for $$\frac{7}{8}$$th of its original mass to...
JEE Main 2022 (Online) 28th July Morning Shift
With reference to the observations in photo-electric effect, identify the correct statements from below : (A) The square...
JEE Main 2022 (Online) 27th July Evening Shift
A metal exposed to light of wavelength $$800 \mathrm{~nm}$$ and and emits photoelectrons with a certain kinetic energy. ...
JEE Main 2022 (Online) 25th July Morning Shift
A source of monochromatic light liberates 9 $$\times$$ 1020 photon per second with wavelength 600 nm when operated at 40...
JEE Main 2022 (Online) 30th June Morning Shift
Nucleus A is having mass number 220 and its binding energy per nucleon is 5.6 MeV. It splits in two fragments 'B' and 'C...
JEE Main 2022 (Online) 24th June Morning Shift
The light of two different frequencies whose photons have energies 3.8 eV and 1.4 eV respectively, illuminate a metallic...
JEE Main 2022 (Online) 24th June Evening Shift
Given below are two statements : Statement I : Davisson-Germer experiment establishes the wave nature of electrons. Stat...
JEE Main 2022 (Online) 25th June Morning Shift
How many alpha and beta particles are emitted when Uranium 92U238 decays to lead 82Pb206 ?...
JEE Main 2022 (Online) 26th June Morning Shift
Given below are two statements : Statement I : In hydrogen atom, the frequency of radiation emitted when an electron jum...
JEE Main 2022 (Online) 27th June Evening Shift
The Q-value of a nuclear reaction and kinetic energy of the projectile particle, Kp are related as :
JEE Main 2022 (Online) 28th June Morning Shift
The electric field at a point associated with a light wave is given by E = 200 [sin (6 $$\times$$ 1015)t + sin (9 $$\tim... JEE Main 2022 (Online) 29th June Evening Shift Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R : Assertion A : Th... JEE Main 2022 (Online) 29th June Morning Shift The half life period of radioactive element x is same as the mean life time of another radioactive element y. Initially ... JEE Main 2021 (Online) 1st September Evening Shift The temperature of an ideal gas in 3-dimensions is 300 K. The corresponding de-Broglie wavelength of the electron approx... JEE Main 2021 (Online) 1st September Evening Shift Consider two separate ideal gases of electrons and protons having same number of particles. The temperature of both the ... JEE Main 2021 (Online) 31st August Evening Shift A free electron of 2.6 eV energy collides with a H+ ion. This results in the formation of a hydrogen atom in the first e... JEE Main 2021 (Online) 31st August Evening Shift A monochromatic neon lamp with wavelength of 670.5 nm illuminates a photo-sensitive material which has a stopping voltag... JEE Main 2021 (Online) 27th August Evening Shift In a photoelectric experiment, increasing the intensity of incident light : JEE Main 2021 (Online) 27th August Morning Shift The de-Broglie wavelength of a particle having kinetic energy E is$$\lambda$$. How much extra energy must be given to t... JEE Main 2021 (Online) 26th August Evening Shift In a photoelectric experiment ultraviolet light of wavelength 280 nm is used with lithium cathode having work function ... JEE Main 2021 (Online) 26th August Morning Shift If 'f' denotes the ratio of the number of nuclei decayed (Nd) to the number of nuclei at t = 0 (N0) then for a collectio... JEE Main 2021 (Online) 27th July Morning Shift When radiation of wavelength$$\lambda$$is incident on a metallic surface, the stopping potential of ejected photoelect... JEE Main 2021 (Online) 25th July Evening Shift The half-life of$${}^{198}Au$$is 3 days. If atomic weight of$${}^{198}Au$$is 198 g/mol then the activity of 2 mg of ... JEE Main 2021 (Online) 25th July Morning Shift Some nuclei of a radioactive material are undergoing radioactive decay. The time gap between the instances when a quarte... JEE Main 2021 (Online) 25th July Morning Shift An electron having de-Broglie wavelength$$\lambda$$is incident on a target in a X-ray tube. Cut-off wavelength of emit... JEE Main 2021 (Online) 20th July Evening Shift The radiation corresponding to 3$$\to$$2 transition of a hydrogen atom falls on a gold surface to generate photoelectr... JEE Main 2021 (Online) 20th July Morning Shift Two identical photocathodes receive the light of frequencies f1 and f2 respectively. If the velocities of the photo-elec... JEE Main 2021 (Online) 17th March Evening Shift The stopping potential in the context of photoelectric effect depends on the following property of incident electromagne... JEE Main 2021 (Online) 16th March Morning Shift The recoil speed of a hydrogen atom after it emits a photon in going from n = 5 state to n = 1 state will be : JEE Main 2021 (Online) 26th February Evening Shift Given below are two statements : one is labeled as Assertion A and the other is labelled as Reason R.Assertion A : An el... JEE Main 2021 (Online) 26th February Morning Shift The stopping potential for electrons emitted from a photosensitive surface illuminated by light of wavelength 491 nm is ... JEE Main 2021 (Online) 25th February Evening Shift The wavelength of the photon emitted by a hydrogen atom when an electron makes a transition from n = 2 to n = 1 state is... JEE Main 2021 (Online) 25th February Evening Shift An$$\alpha$$particle and a proton are accelerated from rest by a potential difference of 200V. After this, their de Br... JEE Main 2021 (Online) 25th February Morning Slot According to Bohr atom model, in which of the following transitions will the frequency be maximum? JEE Main 2021 (Online) 24th February Evening Slot Match List - I with List - II. List I List II (a) Source of microwave frequency ... JEE Main 2021 (Online) 24th February Evening Slot An X-ray tube is operated at 1.24 million volt. The shortest wavelength of the produced photon will be : JEE Main 2021 (Online) 24th February Evening Slot Given below are two statements : Statement I : Two photons having equal linear momenta have equal wavelengths.Statement ... JEE Main 2021 (Online) 24th February Morning Slot Assuming the nitrogen molecule is moving with r.m.s. velocity at 400 K, the de-Broglie wavelength of nitrogen molecule i... JEE Main 2020 (Online) 6th September Evening Slot You are given that Mass of$${}_3^7Li$$= 7.0160u, Mass of$${}_2^4He$$= 4.0026u and Mass of$${}_1^1H$$= 1.0079u. Whe... JEE Main 2020 (Online) 6th September Morning Slot An electron, a doubly ionized helium ion (He++) and a proton are having the same kinetic energy. The relation between th... JEE Main 2020 (Online) 6th September Morning Slot The correct match between the entries in column I and column II are : .tg {border-collapse:collapse;border-spacing:0;}... JEE Main 2020 (Online) 5th September Evening Slot In a photoelectric effect experiment, the graph of stopping potential V versus reciprocal of wavelength obtained is show... JEE Main 2020 (Online) 4th September Evening Slot Find the Binding energy per neucleon for$${}_{50}^{120}Sn$$. Mass of proton mp = 1.00783 U, mass of neutron mn = 1.00... JEE Main 2020 (Online) 4th September Evening Slot Given figure shows few data points in a phot electric effect experiment for a certain metal. The minimum energy for ejec... JEE Main 2020 (Online) 4th September Morning Slot Two sources of light emit X-rays of wavelength 1 nm and visible light of wavelength 500 nm, respectively. Both the sourc... JEE Main 2020 (Online) 3rd September Evening Slot When the wavelength of radiation falling on a metal is changed from 500 nm to 200 nm, the maximum kinetic energy of the ... JEE Main 2020 (Online) 3rd September Morning Slot A particle is moving 5 times as fast as an electron. The ratio of the de-Broglie wavelength of the particle to that of t... JEE Main 2020 (Online) 2nd September Evening Slot Particle A of mass mA =$${m \over 2}$$moving along the x-axis with velocity v0 collides elastically with another parti... JEE Main 2020 (Online) 4th September Morning Slot An electron of mass m and magnitude of charge |e| initially at rest gets accelerated by a constant electric field E. The... JEE Main 2020 (Online) 9th January Evening Slot The energy required to ionise a hydrogen like ion in its ground state is 9 Rydbergs. What is the wavelength of the radia... JEE Main 2020 (Online) 9th January Evening Slot Radiation, with wavelength 6561$$\mathop A\limits^o $$falls on a metal surface to produce photoelectrons. The electron... JEE Main 2020 (Online) 9th January Morning Slot A particle moving with kinetic energy E has de Broglie wavelength$$\lambda $$. If energy$$\Delta $$E is added to its e... JEE Main 2020 (Online) 9th January Morning Slot An electron (of mass m) and a photon have the same energy E in the range of a few eV. The ratio of the de-Broglie wavele... JEE Main 2020 (Online) 7th January Evening Slot The activity of a radioactive sample falls from 700 s–1 to 500 s–1 in 30 minutes. Its half life is close to: ... JEE Main 2020 (Online) 7th January Evening Slot Consider an electron in a hydrogen atom revolving in its second excited state (having radius 4.65$$\mathop A\limits^o \$...
JEE Main 2019 (Online) 12th April Evening Slot
The stopping potential V0 (in volt) as a function of frequency ($$\upsilon$$) for a sodium emitter, is shown in the fig...
JEE Main 2019 (Online) 12th April Morning Slot
A 2 mW laser operates at wavelength of 500 nm. The number of photons that will be emitted per second is : [Given Planck'...
JEE Main 2019 (Online) 10th April Evening Slot
In a photoelectric effect experiment the threshold wavelength of the light is 380 nm. If the wavelentgh of incident ligh...
JEE Main 2019 (Online) 10th April Morning Slot
A particle 'P' is formed due to a completely inelastic collision of particles 'x' and 'y' having de-Broglie wavelengths ...
JEE Main 2019 (Online) 9th April Evening Slot
The electric field of light wave is given as $$\overrightarrow E = {10^{ - 3}}\cos \left( {{{2\pi x} \over {5 \times {... JEE Main 2019 (Online) 9th April Morning Slot A nucleus A, with a finite de-broglie wavelength$$\lambda $$A, undergoes spontaneous fission into two nuclei B and C of... JEE Main 2019 (Online) 8th April Evening Slot Two particles move at right angle to each other. Their de-Broglie wavelengths are$$\lambda _1$$and$$\lambda _2$$resp... JEE Main 2019 (Online) 8th April Morning Slot When a certain photosensitive surface is illuminated with monochromatic light of frequency v, the stopping potential for... JEE Main 2019 (Online) 12th January Evening Slot In a Frank-Hertz experiment, an electron of energy 5.6 eV passes through mercury vapour and emerges with an energy 0.7 e... JEE Main 2019 (Online) 12th January Evening Slot A particle A of mass 'm' and charge 'q' is accelerated by a potential difference of 50 V. Another particle B of mass ' 4... JEE Main 2019 (Online) 12th January Morning Slot In a photoelectric experiment, the wavelength of the light incident on a metal is changed from 300 nm to 400 nm. The dec... JEE Main 2019 (Online) 11th January Evening Slot If the de Broglie wavelength of an electron is equal to the 10–3 times the wavelength of a photon of frequency 6$$ \t...
JEE Main 2019 (Online) 11th January Morning Slot
A metal plate of area 1 $$\times$$ 10–4 m2 is illuminated by a radiation of intensity 16 mW/m2. The work function of t...
JEE Main 2019 (Online) 10th January Evening Slot
The magnetic field associated with a light wave is given, at the origin, by B = B0 [sin(3.14 $$\times$$ 107)ct + sin(6...
JEE Main 2019 (Online) 9th January Evening Slot
Surface of certain metal is first illuminated with light of wavelength $$\lambda$$1 = 350 nm and then, by light of wave...
JEE Main 2019 (Online) 9th January Morning Slot
The de-Broglie wavelength ($$\lambda$$B) associated with the electron orbiting in the second excited state of hydrogen ...
JEE Main 2018 (Online) 16th April Morning Slot
If the de Broglie wavelengths associated with a proton and an $$\alpha$$-particle are equal, then the ratio of velociti...
JEE Main 2018 (Online) 15th April Evening Slot
Two electrons are moving with non-relativistic speed perpendicular to each other. If corresponding de Broglie wavelength...
JEE Main 2018 (Online) 15th April Morning Slot
A Laser light of wavelength 660 nm is used to weld Retina detachment. If a Laser pulse of width 60 ms and power 0.5 kW i...
JEE Main 2017 (Online) 9th April Morning Slot
The maximum velocity of the photoelectrons emitted from the surface is v when light of frequency n falls on a metal surf...
JEE Main 2017 (Online) 8th April Morning Slot
A particle A of mass m and initial velocity v collides with a particle B of mass m/2 which is at rest. The collision is ...
JEE Main 2017 (Offline)
An electron beam is accelerated by a potential difference V to hit a metallic target to produce X–rays. It produces cont...
JEE Main 2017 (Offline)
A photoelectric surface is illuminated successively by monochromatic light of wavelengths $$\lambda$$ and $${\lambda \... JEE Main 2016 (Online) 10th April Morning Slot When photons of wavelength$${\lambda _1}$$are incident on an isolated sphere, the corresponding stopping potential is ... JEE Main 2016 (Online) 9th April Morning Slot Radiation of wavelength$$\lambda ,$$is incident on a photocell. The fastest emitted electron has speed$$v.$$If the w... JEE Main 2016 (Offline) Match List -$${\rm I}$$(Fundamental Experiment) with List -$${\rm II}$$(its conclusion) and select the correct optio... JEE Main 2015 (Offline) The anode voltage of a photocell is kept fixed. The wavelength$$\lambda $$of the light falling on the cathode is gradu... JEE Main 2013 (Offline) This question has Statement 1 and Statement 2. Of the four choices given after the statements, choose the one that best ... AIEEE 2012 This equation has Statement 1 and Statement 2. Of the four choices given after the statements, choose the one that descr... JEE Main 2012 This question has Statement -$$1$$and Statement -$$2$$. Of the four choices given after the statements, choose the on... AIEEE 2011 If a source of power$$4kW$$produces$${10^{20}}$$photons/second, the radiation belongs to a part of the spectrum call... AIEEE 2010 Statement -$$1$$: When ultraviolet light is incident on a photocell, its stopping potential is$${V_0}$$and the max... AIEEE 2010 The surface of a metal is illuminated with the light of$$400nm.$$The kinetic energy of the ejected photoelectrons... AIEEE 2009 Wave property of electrons implies that they will show diffraction effects. Davisson and Germer demonstrated this by dif... AIEEE 2008 Wave property of electrons implies that they will show diffraction effects. Davisson and Germer demonstrated this by dif... AIEEE 2008 In an experiment, electrons are made to pass through a narrow slit of width$$'d'$$comparable to their de Broglie wavel... AIEEE 2008 Photon of frequency$$v$$has a momentum associated with it. If$$c$$is the velocity of light, the momentum is AIEEE 2007 If$${g_E}$$and$${g_M}$$are the accelerations due to gravity on the surfaces of the earth and the moon respectively a... AIEEE 2007 The anode voltage of a photocell is kept fixed. The wavelength$$\lambda $$of the light falling on the cathode is gradu... AIEEE 2006 The time taken by a photoelectron to come out after the photon strikes is approximately AIEEE 2006 The threshold frequency for a metallic surface corresponds to an energy of$$6.2eV$$and the stopping potential for... AIEEE 2006 A photocell is illuminated by a small bright source placed$$1m$$away. When the same source of light is placed$${...
AIEEE 2005
If the kinetic energy of a free electron doubles, it's deBroglie wavelength changes by the factor
AIEEE 2005
According to Einstein's photoelectric equation, the plot of the kinetic energy of the emitted photo electrons from a met...
AIEEE 2004
The work function of a substance is $$4.0$$ $$eV.$$ The longest wavelength of light that can cause photo-electron emiss...
AIEEE 2004
Two identical photo-cathodes receive light of frequencies $${f_1}$$ and $${f_2}$$. If the velocities of the photo electr...
AIEEE 2003
Sodium and copper have work functions $$2.3$$ $$eV$$ and $$4.5$$ $$eV$$ respectively. Then the ratio of the wavelengths ...
AIEEE 2002

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