What Are The Dimensions Of Planck’s Constant?

An electron microscope uses electrons accelerated through 50 kV. Find the de-Broglie wavelength of these electrons. If other factors like numerical aperture etc. are roughly the same, how does the resolving power of an electron microscope compare with that of an optical microscope which uses variable light?

The force exerted by a magnetic field on a charged particle is independent of the

The monoenergetic electron beam electron speed of  is subjected to a magnetic field of  normal to the beam velocity. What is the radius of the circular path traced by the beam? Given e/m  forelectron .

Two parallel plates are placed 5 cm apart in an evacuated tube and a potential difference of 200 V is applied across them? What is the force experienced by an electron at rest in the region between the plates?   

The first scientist to measure the charge to mass ratio of the electron was

In Thomson’s experiment for determining , the potential difference between the cathode and the anode (in the accelerating column) is the same as that between the deflecting plates (in the region of crossed fields). If the potential difference is doubled, by what factor should the magnetic field be increased to ensure that the electron beam remains undeflected?

The minimum wavelength of X-rays emitted from an X-ray tube operating at a voltage of 10⁴ volts is roughly equal to  

The energy in monochromatic X-rays of wavelength 1 Å is roughly equal to

What is the unit of Planck’s constant?

An X-rays tube produces X-rays whose shortest wavelength is 0.2475 Å. The operating voltage of the tube must be