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

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

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

How many lines can pass through one given point?

In a Young's double slit experiment ,light has a frequency of 6 xx 10^(14) s^(-1) .The distance between the centres of adjacent brigth fringes is 0.75 mm. If the screen is 1.5m away then, find the distance between the slits.

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.

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

The circle passing through the point ( -1,0) and touching the y-axis at (0,2) also passes through the point.

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