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Show that gravitational force within a nuclei is negilible compared with the electric repulsion.

Electric Field Repulsion - 90N Gravitation Field Attraction - 7.3x10^-35N

Answered by Matthew S. • Physics tutor

2008 Views

Photons with 605 THz frequency strike metal of 1.2eV work function. Calculate the maximum energy of photoelectrons and their velocity. What amount of energy is necessary to stop all photoelectrons? (Planck's constant. electron mass and charge are given)

Start off by converting all given data into SI units to avoid confusion later on. The photoelectric effect happens when photons with energy larger than work function strike metal, thus releasing the elect...

Answered by Ignas V. • Physics tutor

2052 Views

The amplitude of a simple harmonic oscillator has decreased from 40cm to 38cm. What percentage of energy did the harmonic oscillator lose?

It is recommended to start off by converting all given data into SI units to avoid confusion later on. Write down the total energy of the system and that it is conserved: E(tot)= KE+PE and KE=(mv^2)/2; PE...

Answered by Ignas V. • Physics tutor

2016 Views

calculate the resistivity in a 1.2m length of cylindrical wire with radius 1cm. The resistance of the wire is 0.01 kilo Ohms

The primary equation in this calculation is rho = RA/L Where rho is resistivity, A is cross sectional area, L is length, and R is resistance

The resistance and length are given in the question. Res...

Answered by Calum S. • Physics tutor

2957 Views

The LHC accelerates protons to a speed of 0.999999991c around a 27km ring. Due to relativistic effects, their mass increases. Given that the magnetic fields used are 8T, calculate this mass. What is the total energy of an LHC beam containing 3e14 protons?

Balancing the centripetal force mv^2/r with the force experienced due to motion in a magnetic field qvB: m = qBr/v = qBC/2piv (C circumference). Putting in numbers: m = 1.83e-23 kg (~11,000 mass of proton...

Answered by Tutor48526 D. • Physics tutor

2536 Views