Explanation

• Weight is a vector quantity
• Because it is a force defined as the product of mass and the acceleration due to gravity (W = mg).
• It has both magnitude (amount of force) and direction (downward, towards the center of the Earth)

Additional information 

Mass,  Time, and temperature are scalar quantities

Last updated on 09-03-2026

Explanation

• A covalent bond is formed between two non-metal atoms. 
• Examples: Molecule formation like H₂O and CO₂.
• Properties: Generally results in lower melting/boiling points compared to ionic compounds.
• These atoms achieve stability by sharing one or more pairs of valence electrons to fill their outer shells

Last updated on 09-03-2026

Explanation

• A carbon microphone does not depend on the magnetic effect of current.
• Based on the variation of electrical resistance
• It converts sound vibrations into electrical signals 

Additional information 

Devices like electromagnets, electric bells, and ammeters work due to the magnetic effect of current.

Last updated on 09-03-2026

Explanation

Elements or compounds that combine in a chemical reaction are called reactants.

Explanation

• The product of mass and velocity is known as momentum. P = MV
• If m is an object's mass and v is its velocity (also a vector quantity), then the object's momentum p is: p=mv
• It is a vector quantity.
• It having both magnitude and direction.
• Common symbols: p, p
• SI unit: kg⋅m⋅s−1
• Dimension MLT^−1

Last updated on 09-03-2026

Explanation

• Carnivores are animals that eat only meat, primarily from other animals.
• Examples of carnivores include lions, tigers, bears, wolves, and sharks.

Additional information:

• Animals that eat plants exclusively are herbivores.
• Animals that eat both plants and meat are called omnivores.

Last verified on 07-03-2026

Explanation

• Amphibians are animals that live both in water and on land.
• Most amphibians lay their eggs in water because their eggs do not have a protective shell.
• Examples of Amphibians: Frog, Toad, Salamander, Newt, Caecilian

Last verified on 07-03-2026

Explanation

• Protons and neutrons form the nucleus of an atom.
• Together, they are called nucleons because they are nuclear particles.

Additional information:

• Nucleons determine the mass of an atom.
• Isotopes are atoms of the same element with different number of neutrons.

Last verified on 07-03-2026

Explanation

• Coal is a fossil fuel because it is formed from the remains of dead plants
• It is a major source of energy.
• Used for electricity generation and industrial processes.

Explanation

• Petroleum, Coal, and Natural gas are all fossil fuels. 
• They are non-renewable energy sources 
• Major contributors to global energy production.
• Coal: A solid fossil fuel primarily derived from ancient swamp plants.
• Petroleum (Oil): from the remains of marine microorganisms like plankton.
• Natural gas: Composed of methane, often found in underground deposits alongside petroleum or coal

Last updated on 06-March-2026