NEET Physics Dual Nature of Matter and Radiation MCQs

If light of frequency $4

u_0$(where$

u_0$is the threshold frequency) is incident on a metal, the maximum kinetic energy of the emitted electrons is$K_1$. When the frequency is changed to$8

u_0$, the maximum kinetic energy becomes$K_2$. What is the ratio of$K_1$to$K_2$?

The threshold frequency of a metal is $

u_0$. When light of frequency$2.5

u_0$is incident, the maximum velocity of emitted electrons is$v$. If the frequency is increased to$4

u_0$, what will be the new maximum velocity?

Light of frequency $

u$is incident on a metal with threshold frequency$

u_0$. If$

u = 3

u_0$, and the maximum kinetic energy of emitted electrons is$K$, what will be the maximum kinetic energy if$

u$ is doubled?

A metal surface has a threshold frequency $

u_0$. When light of frequency$2

u_0$is incident, the stopping potential is$V_0$. What will be the stopping potential if the incident frequency is increased to$3

u_0$?

A proton of mass $m$ with an initial velocity $\overrightarrow{V} = V_0 \hat{i} \left( V_0 > 0 \right)$ enters an electric field $\overrightarrow{E} = -E_0 \hat{i}$ ($E_0 =$ constant $> 0$). If $\lambda_0$ is its de-Broglie wavelength initially, then its de-Broglie wavelength at time $t$ is:

An alpha particle of mass $4m$ with an initial velocity $\overrightarrow{V} = 2V_0 \hat{i}$ enters an electric field $\overrightarrow{E} = -2E_0 \hat{i}$. If $\lambda_0$ is its initial de-Broglie wavelength, what is its wavelength after a time $t$?

An electron with initial de-Broglie wavelength $\lambda_0$ is moving with velocity $V_0 \hat{i}$ and enters a region with electric field $-E_0 \hat{i}$. How much time will it take for its de-Broglie wavelength to become $2\lambda_0$?

An electron enters an electric field $\overrightarrow{E} = -E_0 \hat{i}$ with an initial velocity $V_0 \hat{i}$. If its initial de-Broglie wavelength is $\lambda_0$, what will be the percentage change in its de-Broglie wavelength after a time $t = \frac{mv_0}{4eE_0}$?

A proton with de-Broglie wavelength $\lambda_0$ enters a region of uniform electric field $\vec{E} = -E_0\hat{i}$. Which of the following graphs correctly represents the variation of its de-Broglie wavelength ($\lambda$) with time ($t$)?

An electron is accelerated from rest through a potential difference of $V$ volts. If the de Broglie wavelength of the electron is $1.227 imes 10^{-2}$ nm, the potential difference is: