20 waves pass through a point in 2 seconds. If the distance between one crest and adjacent through it 1.5m, calculate wavelength.

20 waves pass through a point in 2 seconds. If the distance between one crest and adjacent through it 1.5m, calculate the frequency

The distance between a consecutive crest and trough is x. Then wavelength of the wave is

Distance between a consecutive crest and trough is 5 cm. The wave length of wave is

In a Young's double slit experiment ,the distance between the slits and the screen is 1 m.If the distance between the slits is 5 mm,the fringe width is found to be 0.1 mm.Calculate the wavelength of the light used.

How many lines can pass through one given point?

Electromagnetic waves of frequency 5 xx 10^(14) Hz are passed through a liquid.The wavelength of the waves in liquid is measured to be 4.5 xx 10^(-7) m . Calculate the wavelength of e.m. waves in vacuum,

A ray of light passing through the point (1, 2) reflects on the x-axis at point A and the reflected ray passes through the point (5, 3). Find the coordinates of A.

In a plane there are 37 straight lines, of which 13 passes through the point A and 11 passes through point B. Besides, no three lines passes through one point no line passes through both points A and B and no two are parallel, then find the number of points of intersection of the straight line.

If a line passing through two points (-2,4,-5) and (1,2,3) then its direction cosines will be :