JEE Main 2021 (Online) 31st August Evening Shift | Dual Nature of Radiation Question 75 | Physics

Consider two separate ideal gases of electrons and protons having same number of particles. The temperature of both the gases are same. The ratio of the uncertainty in determining the position of an electron to that of a proton is proportional to :-

$${\left( {{{{m_p}} \over {{m_e}}}} \right)^{3/2}}$$

$$\sqrt {{{{m_e}} \over {{m_p}}}} $$

$$\sqrt {{{{m_p}} \over {{m_e}}}} $$

$${{{m_p}} \over {{m_e}}}$$

JEE Main 2021 (Online) 31st August Morning Shift

MCQ (Single Correct Answer)

-1

A moving proton and electron have the same de-Broglie wavelength. If K and P denote the K.E. and momentum respectively. Then choose the correct option :

K_p < K_e and P_p = P_e

K_p = K_e and P_p = P_e

K_p < K_e an P_p < P_e

K_p > K_e and P_p = P_e

JEE Main 2021 (Online) 27th August Evening Shift

MCQ (Single Correct Answer)

-1

A monochromatic neon lamp with wavelength of 670.5 nm illuminates a photo-sensitive material which has a stopping voltage of 0.48 V. What will be the stopping voltage if the source light is changed with another source of wavelength of 474.6 nm?

0.96 V

1.25 V

0.24 V

1.5 V

JEE Main 2021 (Online) 27th August Morning Shift

MCQ (Single Correct Answer)

-1

In a photoelectric experiment, increasing the intensity of incident light :

increases the number of photons incident and also increases the K.E. of the ejected electrons

increases the frequency of photons incident and increases the K.E. of the ejected electrons

increases the frequency of photons incident and the K.E. of the ejected electrons remains unchanged

increases the number of photons incident and the K.E. of the ejected electrons remains unchanged