TN State Board 10th Science Question Paper 2022

A convex lens forms a real and inverted image of the same size as the object when the object is placed at $2f$ (twice the focal length). In this case, the image is also formed at $2f$ on the other side of the lens. At $f$ the image is formed at infinity, at infinity the image is at the focus and highly diminished, and between $f$ and $2f$ the image is real, inverted and enlarged.

A molecule made of similar kind of atoms is called a homo atomic molecule. "Homo" means same, so the atoms present are of the same element. Monoatomic means a single atom, hetero atomic means different kinds of atoms, and polyatomic refers to a molecule with many atoms, not necessarily of the same kind.

A binary solution has $2$ components. 'Binary' means two, so the solution contains two substances: a solute and a solvent.

Current is given by $I=\frac{Q}{t}$. Here, $Q=12\,\text{C}$ and $t=5\,\text{s}$. So, $I=\frac{12}{5}=2.4\,\text{A}$. Therefore, the current through the bulb is $2.4\,\text{A}$.

Rectified spirit is an aqueous solution containing about $95.5\%$ ethanol. It is ethanol with a small amount of water left after rectification.