Light of wavelength 2475 Å is incident on barium. Photoelectrons emitted describe a circle of radius 100 cm by a magnetic field of flux density Tesla. Work function of the barium is (Given

If a voltage applied to an X-ray tube is increased to 1.5 times the minimum wavelength of an X-ray continuous spectrum shifts by . The initial voltage applied to the tube is

The figure shows different graphs between stopping potential and frequency (n) for photosensitive surface of cesium, potassium, sodium and lithium. The plots are parallel. Correct ranking of the targets according to their work function greatest first will be

f(x) = is continuous at x = 2 then k =

is continuous on

The value of f (0) so that f(x) = is continuous at x = 0 is

We have to be careful that denominator is not zero. We have to readjust the function in a way we will not get zero at denominator for the function to be continuous at that point. And, we have to know different formulas of limit.

Ifthen atis

A point moves so that the ratio of its distances from two fixed points is constant Its Iocus is a

The points , , and are

The shortest distance of the point from on the ‐axis is equal to

If cos + cos = 0 = sin + sin then cos ( - ) =

If and are two points, the direction cosines of the line are

The equation of a plane passing through the line of intersection of the planes and and parallel to the line is

A directed line segment angles with the coordinate axes The value of is always equal to

A point moves so that the rra io of its distances from two fixed points is constant Its Iocus is a