The area of a square plate is measured as A0 when it is at rest with respect to an observer. If the square plate moves with respect to the observer along one of its diagonals with a speed of c√2, then the area measured by the observer is αA0. The value of α is:

A globe of rest radius R0, carrying identifiable surface markings, moves with speed v in a direction perpendicular to the line joining it to a distant observer. A photograph is taken when the globe is exactly at the position of closest approach. After developing the film, what will the observer see?

An atom emits light of angular frequency ω0 in its own rest frame. The atom moves with speed v along the line joining it to a stationary observer. Which option correctly gives the observed angular frequency ω when the motion is directly away from or towards the observer?