The wavelengths of two sound notes in air are $\frac{40}{195} ~m$ and $\frac{40}{193} ~m$. Each note produces $9$ beats per second separately with a third note of fixed frequency. The velocity of sound in air in $m/s$ is

Assertion: The isothermal curves intersect each other at a certain point.
Reason: The isothermal change takes place slowly,so,the isothermal curves have very little slope.

Which of the following is not an essential amino acid?

The angle of a prism is $A.$ One of its refracting surfaces is silvered. Light rays falling at an angle of incidence $2A$ on the first surface return back through the same path after suffering reflection at the silvered surface. The refractive index $\mu$ of the prism is

The displacement equations of two waves are given as $y_1 = 10 \sin(3\pi t + \pi/3)$ and $y_2 = 5(\sin 3\pi t + \sqrt{3} \cos 3\pi t)$. What is the ratio of their amplitudes?

If one of the lines of the pair $ax^2 + 2hxy + by^2 = 0$ bisects the angle between the positive directions of the axes,then $a, b, h$ satisfy the relation: