The acidity of oxyacids like HNO\(_3\), HClO\(_4\), and HClO\(_3\) depends on the electronegativity of the central atom and the number of oxygen atoms attached to it.
The greater the number of oxygen atoms and the higher the electronegativity of the central atom, the stronger the acid. - HClO\(_4\) is the strongest acid because chlorine is highly electronegative and has the most oxygen atoms attached to it.
HNO\(_3\) is stronger than HClO\(_3\) because the nitrogen atom is more electronegative than chlorine, and nitric acid has more oxygen atoms than chlorous acid.
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: $g = 10\,\text{m s}^{-2}$) 
Two circular discs of radius \(10\) cm each are joined at their centres by a rod, as shown in the figure. The length of the rod is \(30\) cm and its mass is \(600\) g. The mass of each disc is also \(600\) g. If the applied torque between the two discs is \(43\times10^{-7}\) dyne·cm, then the angular acceleration of the system about the given axis \(AB\) is ________ rad s\(^{-2}\).
