Physics Test - ...

The surface of a metal is illuminated with the light of \(400 \mathrm{~nm}\). The kinetic energy of the ejected photoelectrons was found to be \(1.68 \mathrm{eV}\). The work function of the metal is: \((h c=1240 \mathrm{eVnm})\)

What happens to the capacitance of a parallel plate capacitor when the area of the plates, as well as the distance between them, is halved?

For the equation F ∝ A^av^bd^c, where F is the force, A is the area, v is the velocity and dd is the density, the values of a, b, and c are respectively.

Two photons of the same frequency are produced due to the annihilation of a proton and antiproton. Wavelength of the proton so produced is:

The ratio of kinetic energy and the potential energy of the satellite rotating around the earth is:

Monochromatic light of frequency \(6.0 \times 10^{14} \mathrm{~Hz}\) is produced by a laser. The power emitted is \(2.0 \times 10^{-3} \mathrm{~W}\). How many photons per second, on average, are emitted by the source?

What is the force required to produce an acceleration of \(9.8 \mathrm{~m} / \mathrm{s}^{2}\) on a body of weight \(9.8 \mathrm{~N}\) ? Take \(\mathrm{g}=9.8 \mathrm{~m} / \mathrm{s}^{2}\).

Which of the following effect is not related to the electromagnetic waves?

Light from a point source in the air falls on a spherical glass surface (μ=1.5 and radius of curvature 20 cm). The distance of the light source from the glass surface is 100 cm. The position where the image is formed is: