An electron is accelerated from rest through a potential difference of V volt. If the de-Broglie wavelength of the electron is 1.227 $$ \times $$ 10^-2 nm, the potential difference is :

An electron is accelerated through a potential difference of 10,000 V. Its de Broglie wavelength is (nearly) : (m_e = 9 $$ \times $$ 10^–31 kg)

An electron of mass m with an initial velocity $$\overrightarrow v = {v_0}\widehat i$$ (v₀ > 0) enters an electric field $$\overrightarrow E = - {\overrightarrow E _0}\widehat i$$ (E₀ = constant > 0) at t = 0. If $$\lambda $$₀ is its de-Broglie wavelength initially, then its de- Broglie wavelength at time t is

When the light of frequency 2$${\upsilon _0}$$ (where $${\upsilon _0}$$ is threshold frequency), is incident on a metal plate, the maximum velocity of electrons emitted is v₁ . When the frequency of the incident radiation is increased to 5$${\upsilon _0}$$ , the maximum velocity of electrons emitted from the same plate is v₂ . The ratio of v₁ to v₂ is