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Given   $F\propto \frac{1}{r^n}$

$m{\omega }^{2}R=\frac{K}{R^n}$

$?\frac{m.4{\pi }^{2}R}{T^2}=\frac{K}{R^n}$

$?T^2\propto R^{n+1}$

$T\propto R^{\frac{n+1}{2}}$

Angular momentum imparted to sprinkler per

$second=vr\frac{dm}{dt}=\frac{0.6}{60}\times 0.5\times 1=0.005N.m$

$?l\frac{d\omega }{dt}=0.005$

$?\frac{d\omega }{dt}=\frac{0.005}{500\times {10}^{-7}}$

$=100\frac{rad}{s^2}$

Applying conservation of momentum for collision of blocks

$2mv+0=3m{v}^{\text{'}}$

$?v^{\text{'}}=\frac{2v}{3}\dots \left(1\right)$

Now, from conservation of energy

$\frac{1}{2}\times 3m\times {v^{\text{'}}}^2=\frac{1}{2}k{x}_0^2$

$x_0=\sqrt[]{\frac{3m{v}^{\text{'}2}}{k}}=v\text{'}\sqrt[]{\frac{3m}{k}}$

$=\frac{2v}{3}\sqrt[]{\frac{3m}{k}}=v\sqrt[]{\frac{4m}{3k}}$

In NEET exam, there can be 1 to 2 questions from redox reactions, carrying 4-8 marks. The weightage is around 2% to 4%. In JEE Main, the weightage of this chapter is from 3.3% to 4-6%. You can expect nearly 1 to 2 questions from this chapter.

The applications of redox reactions include in cellular respiration, and batteries. In industries, these are used in the chemical production, metal extraction and water treatment. 

The redox reactions are significant for some of the basic functions of life such as respiration, photosynthesis, corrosion or rusting and combustion.

There are four types of redox reactions. These are combination, Decomposition, Displacement, and Disproportionation.
In the combination redox reaction, two or more substances form a single product, in decomposition reactions, a compound breaks down into two or more substances. When one element in a compound replaces another, it is called displacement reactions. When simultaneously, one substance is oxidized and reduced, the reaction is known as the disproportionation redox reaction.

In a chemical reaction when electrons transfer simultaneously between substances, it is called as the redox reaction.  In redox reaction, one substance gets oxidized by losing electrons and another substance reduces by gaining the electrons. These two processes together occurs in a redox reaction.

For normal emergence

$r=A$

From Snell’s Law

$\frac{\sin ?i}{\sin ?r}=\frac{\mu }{1}$

$?\sin ?i=\sqrt[]{2}\sin ?{30}^0$

$?i={45}^0$

Balancing torque about COM

$T_A\left(\frac{l}{2}\right)=T_B\left(\frac{l}{6}\right)$

$?\frac{T_A}{T_B}=\frac{1}{3}$

Moles of $AI=\frac{5.4}{27}=\frac{1}{5}$ $\frac{}{}\frac{}{}$

$q=nC?T=\frac{1}{5}\times 24\times 30=144J$

Kindly consider the following figure

Fraction of molecule having energy $E_a$ or greater than $E_a=e^{\frac{-E_a}{RT}}$  

$\theta =\omega t$

$2\pi =\left(\frac{V}{3R}\right)T$

$?t=\frac{6\pi R}{V}$

The distance travelled by car in this time is

$s=vt$

$?s=v\left(\frac{6\pi R}{V}\right)$

$=6\pi R$

In case of gas in gas, true solution will be always formed.

$C{a}_3{\left(P{O}_4\right)}_2\to 3C{a}^{2+}+2P{O}_4^{3-}$