Wave Optics — Physics STD 12 Science — Question

Write briefly the underlying principle used in Davison-Germer experiment to verify wave nature of electrons experimentally. What is the de-Broglie wavelength of an electron with kinetic energy (of).120 ev? Write briefly the underlying principle used in Davison-Germer experiment to verify wave nature of electrons experimentally. What is the de-Broglie wavelength of an electron with kinetic energy (of).120 ev?

Why should the objective of a telescope have large focal length and large aperture? Justify your answer.

Can the entire charge of a charged object 'A' be transferred to another object 'B'? If yes then how would it be possible, if not then why?

A small sphere of radius r₁ and charge q₁ is enclosed by a spherical shell of radius r₂ and charge q₂. Show that if q₁ is positive, charge will necessarily flow from the sphere to the shell (when the two are connected by a wire) no matter what the charge q₂ on the shell is.

A spherical surface of radius 30cm separates two transparent media A and B with refractive indices 1.33 and 1.48 respectively. The medium A is on the convex side of the surface. Where should a point object be placed in medium A so that the paraxial rays become parallel after refraction at the surface?

Two vectors have magnitudes 2m and 3m. The angle between them is 60°. Find:

1. The scalar product of the two vectors.
2. The magnitude of their vector product.

Three capacitors each of capacitance 9 pF are connected in series.

1. What is the total capacitance of the combination?
2. What is the potential difference across each capacitor if the combination is connected to a 120 V supply?

Define the term ‘linearly polarised light’.
When’ does the intensity of transmitted light become maximum, when a polaroid sheet is rotated between two crossed polaroids?

Find the moment of inertia of a pair of spheres, each having a mass m and radius r, kept in contact about the tangent passing through the point of contact.