(a) the energy of photon incident on a material is 1.42 ev. ( determine the minimum frequency of an incident photon that can interact with a valence electron and elevate the electron to become free. (ii) what is the corresponding wavelength? (b) repeat part (a) for a photon energy of 1.12 ev.

The magnitude of the magnetic field at a certain distance from a long, straight conductor is represented by b. what is the magnitude of the magnetic field at twice the distance from the conductor? a. at twice the distance, the magnitude of the field is 4b. b. at twice the distance, the magnitude of the field is 2b. c. at twice the distance, the magnitude of the field is b/2.d. at twice the distance, the magnitude of the field is b/4.e. at twice the distance, the magnitude of the field remains equal to b.