Dual Nature of Radiation · Physics · KCET
MCQ (Single Correct Answer)
The anode voltage of a photocell is kept fixed. The frequency of the light falling on the cathode is gradually increased. Then the correct graph which shows the variation of photo current I with the frequency $v$ of incident light is
Light of energy $E$ falls normally on a metal of work function $\frac{E}{3}$. The kinetic energies $K$ of the photo electrons are
The photoelectric work function for photo metal is 2.4 eV . Among the four wavelengths, the wavelength of light for which photoemission does not take place is
A 60 W source emits monochromatic light of wavelength 662.5 nm. The number of photons emitted per second is
In an experiment to study photoelectric effect the observed variation of stopping potential with frequency of incident radiation is as shown in the figure. The slope and $$y$$-intercept are respectively
The energy gap of an LED is $$2.4 \mathrm{~eV}$$. When the LED is switched ON, the momentum of the emitted photons is
The kinetic energy of the photoelectrons increases by $$0.52 \mathrm{~eV}$$ when the wavelength of incident light is changed from $$500 \mathrm{~nm}$$ to another wavelength which is approximately
The de-Broglie wavelength of a particle of kinetic energy $$K$$ is $$\lambda$$, the wavelength of the particle, if its kinetic energy $$\frac{K}{4}$$ is
In a photo electric experiment, if both the intensity and frequency of the incident light are doubled, then the saturation photoelectric current
The work-function of a metal is 1 eV. Light of wavelength $$3000 \mathop A\limits^o$$ is incident on this metal surface. The velocity of emitted photoelectrons will be
A proton moving with a momentum $$p_1$$ has a kinetic energy $$1 / 8$$th of its rest mass-energy. Another light photon having energy equal to the kinetic energy of the possesses a momentum $$p_2$$. Then, the ratio $$\frac{p_1-p_2}{p_1}$$ is equal to
According to Einstein's photoelectric equation to the graph between kinetic energy of photoelectrons ejected and the frequency of incident radiation is
A hot filament liberates an electron with zero initial velocity. The anode potential is $$1200 \mathrm{~V}$$. The speed of the electron when it strikes the anode is
The de-Broglie wavelength associated with electron of hydrogen atom in this ground state is
The following graph represents the variation of photocurrent with anode potential for a metal surface. Here $$I_1, I_2$$ and $$I_3$$ represents intensities and $$\gamma_1, \gamma_2, \gamma_3$$ represent frequency for curves $$1,2$$ and $$3$$ respectively, then
An electron is moving with an initial velocity $$\mathbf{v}=v_0 \hat{\mathbf{i}}$$ and is in a uniform magnetic field $$\mathbf{B}=B_0 \hat{\mathbf{j}}$$. Then its de-Broglie wavelength
Light of certain frequency and intensity incident on a photosensitive material causes photoelectric effect. If both the frequency and intensity are doubled, the photoelectric saturation current becomes
