We know that \(v = fλ\)
Putting the values,
\(\frac{3 \times 10^8}{\sqrt{6.25}} = f \times 20\times 10^{-3}\)
\(⇒ f = 6 \times 10^9 Hz\)
Which one of the following graphs accurately represents the plot of partial pressure of CS₂ vs its mole fraction in a mixture of acetone and CS₂ at constant temperature?

In the given figure, the blocks $A$, $B$ and $C$ weigh $4\,\text{kg}$, $6\,\text{kg}$ and $8\,\text{kg}$ respectively. The coefficient of sliding friction between any two surfaces is $0.5$. The force $\vec{F}$ required to slide the block $C$ with constant speed is ___ N.
(Given: $g = 10\,\text{m s}^{-2}$) 
The main properties of waves are as follows –