Explanation

• 1 second → Half oscillation of a seconds pendulum
• 0.1 second → Very fast oscillating system
• 2 seconds → Time period of a seconds pendulum
• 0.5 second → Faster pendulum, shorter length than seconds pendulum

Explanation

The troposphere is the lowest layer of the atmosphere, directly in contact with the Earth's surface.

It is where weather occurs and contains about 75% of the atmosphere’s mass.

The principle constituent of the atmosphere of the Earth is called Nitrogen.

Explanation

Appreciable means نوٹ کرنے یا ناپنے کے لیے بڑے یا کافی اہم

Measurable means نوٹ کرنے یا ناپنے کے لیے بڑے یا کافی اہم

Explanation

The S-block includes Group 1 (alkali metals) and Group 2 (alkaline earth metals) along with helium, totaling 14 elements.

These elements have their outermost electrons in the s-orbital.

Additional Information:

P-block → 6 groups (13–18) → 38 elements

D-block → Transition metals (Groups 3–12) → 40 elements

F-block → Lanthanides + Actinides → 28 elements

Explanation

Cultivation means means پودوں کی تیاری اور ان کی پرورش کا عمل - بنیادی طور پر ان میں اضافہ

Growing means پودوں کی تیاری اور ان کی پرورش کا عمل - بنیادی طور پر ان میں اضافہ

Explanation

Asset means کوئی قیمتی یا فائدہ مند چیز - ایک طاقت یا فائدہ

Advantage means کوئی قیمتی یا فائدہ مند چیز - ایک طاقت یا فائدہ

Explanation

Aldol condensation can occur between two aldehydes, two ketones, or an aldehyde and a ketone if they have at least one α-hydrogen.

The reaction forms a β-hydroxy compound, which often dehydrates to an α,β-unsaturated product.

Explanation

Radon (Rn) is a radioactive noble gas that is formed naturally from the decay of uranium and thorium in the Earth’s crust.

It is colorless, odorless, and radioactive.

It is often found in soil and rock.

Explanation

Silicon has the highest melting point among the given elements due to its giant covalent structure.

It requires more energy to break the strong covalent bonds.

Explanation

Nitrobenzene reacts slower than benzene in electrophilic substitution due to the electron-withdrawing nitro group.

The NO₂ group deactivates the benzene ring, making it less reactive toward electrophiles.