Units and Measu...

Which method is used by astronomers to calculate how far the star is?

The dimensions of Planck's constant is the same as the product of

The physical quantity having the dimensions $$\displaystyle \left[ { M }^{ -1 }{ L }^{ -3 }{ T }^{ 3 }{ A }^{ 2 } \right] $$ is :

The dimensional formula for Reynold's number is ________.

Parallax method is useful 

Which of the following is the parallax angle in the shown diagram?

Parallax method is suitable for the measurement of:

What is the approximation made in the parallax method?

$$1$$ femtometre is equivalent to 

The relation between $$\theta$$ , $$b$$ and $$D$$ is:
(where $$\theta$$ is the parallax angle, $$b$$ is the distance between two points of separation, $$D$$ is the distance of source from any point of observation)