List of top Geophysics Questions on Modern Physics

Given below are two statements:
Assertion (A): In photoelectric effect there is no time lag \((\sim10^{-9}s)\) between incidence of photon and emission of photoelectrons.
Reason (R): This is because electromagnetic wave energy is concentrated in photons and not spread out, so there should be no delay in the emission of electrons.

Which of the following is correct in Compton effect?
A. X-ray photon strikes an electron which is at rest,
B. Maximum Compton shift is few metres,
C. Maximum Compton shift is \(0.0484\ \text{\AA}\),
D. An electron strikes on metal surface.

Given below are two statements:
Assertion (A): The laws of Physics all take the same identical form for all frames of reference in uniform relative motion, for all inertial frame of references.
Reason (R): This is due to absence of an absolute or fixed frame of reference.

The Rayleigh Jean's Law,
(A) agrees well with experimental results at low frequencies.
(B) agrees well with experimental results at longer. wavelengths.
(C) shows ultra-violet catastrophe at higher frequencies.
(D) agrees well with experimental results at higher frequencies.
Choose the correct answer from the options given below:

X- rays of wavelength 15 pm are scattered from a target. The wavelength of the X-rays scattered through 60° is (Given compton wavelength = 2.426 pm)

In Photo- electric effect
(A) There is no time interval (very small ~ 10⁻⁹s) between incidence of light and emissions of photo electrons.
(B) Higher the frequency of light, more is the kinetic energy of photo electrons emitted.
(C) A bright light yields more photo-electrons than dim light.
(D) Blue light emits slower electrons than red light.
Choose the correct answer from the options given below: