Physics

From first law of thermodynamics

$?W=?Q-?U$

$?Q=n{C}_p?T$

$?U=n{C}_v?T$

$?W=n(C_p-C_v)?T$

$\frac{?Q}{?W}=\frac{\gamma }{\gamma -1}\left. [\frac{C_p}{C_p}=\gamma \right]$

This happens due to the lack of electrons. Metals have a solid flow of electric current in their bodies due to the presence of free electrons moving throughout. These electrons are responsible for carrying electric charges which makes them a good conductor of electricity. however, the lack of these electrons in non-metals makes them an insulator.

From F.B. Ds of

$9kg\to 90-T_1=9a\dots .\left(1\right)$

$6kg\to T_1-T_2=6a\dots ..\left(2\right)$

$5kg\to T_2-50=5a\dots ..\left(3\right)$

$\left(1\right)+\left(2\right)+\left(3\right)$

$40=20a?a=2m/s^2$

For minima

$d\cos ?\theta =\left(n+\frac{1}{2}\right)\lambda$

$?\cos ?\theta =\frac{2n+1}{8}$

$?n=-4,-3,-2,-1,0,1,2,3$

$?8$ minimas

As per electric current, the key difference between an electron and a proton is that electrons are directly responsible for carrying electric current. On the other hand, protons do not contribute in the passage of current since they are held tightly by the nucleus in the centre of the atom.

In JEE Main exam, it is a significant chapter. There can be 6 to 8 questions from this chapter, a weightage of nearly 6.6%.

The exact weightage varies from year to year. This chapter comes under a broader category which can be "Magnetism" or "Modern Physics". In NEET exam, the chapter's weightage is low to moderate and there can be 6-7% of questions from this chapter.

The chapter is one of the small and easy chapter of class 12 Physics. It includes - properties of magnetic materials, magnetic dipoles, and Earth's magnetic field.

When the electric charges moves, it creates attraction or repulsion. It creates magnetic forces and fields and called magnetism. The term "magnetism and matter" talks about the way magnetic forces and matter interact.