Atomic and Nuclear Physics Answers

what is the reaction force of centripetal force?

WHY ARE THE BRIDGE DECLARED UNSAFE AFTER A LONG USE?

Hi
Theres a few questions i need to checkmy work on. the questions are
1.What is the frequency of a photon with a wavelength of 1040 nm. Report your answers to three significant digits.
The frequency is = _________ s-1

2.What is the energy of a photon with a wavelength of 260 nm. Report your answers to three significant digits.

3.In the Bohr model of the hydrogen atom, the n=1 to n=4 electronic transition corresponds with an ______ of energy; the change in the energy of the atom in this process is a _______ value.

why the spin of electron is half ?

What is the difference between an intrinsic and extrinsic semi conductor material? What is doping?

The electron beam in a television tube consists of electrons accelerated from rest through a potential difference of about 20 000V. What is the speed of the electrons? (Ignore relativistic effects). Electron rest mass is
9.11×10−31
kg and electronic charge is
1.6×10−19C

A certain metal when irradiated with light (frequency =3.2*10^16Hz) emits photoelectron with twice kinetic energy as did photoelectrons when the same metal is irradiated by light ( frequency =2.0*10^16Hz). Calculate frequency of electron?
(1)1.2*10^14Hz
(2)8.0*10^15Hz
(3)1.2*10^16Hz
(4)4.0*10^12Hz

What is the probability that a donor atom at energy ED is ionized ?

The Fermi energy for silver is 5.48 eV. Which of the following is true : (a) the density
of energy states is greater at 2 eV (b) the density of energy states is greater at 6 eV or
(c) the density of energy states is same near both energies ?

Write down the electronic configuration of the Si atom. What type of bonding would
you expect to find in Si?