Explanation

Metamorphic rocks are formed from pre-existing rocks (igneous, sedimentary, or older metamorphic rocks).

They are changed by high heat and/or pressure without melting.

Common examples include marble (from limestone) and gneiss (from granite).

The process is called metamorphism, meaning “change in form.”

Explanation

Aluminum is a metal that can be recycled many times without losing its properties.

Additional information:

• Recycling 1 ton of aluminum saves up to 95% of the energy required to make new aluminum.
• Aluminum is widely used in cans, foils, and packaging, making it highly recyclable.

Last verified on 16-01-2026

Explanation

A mixture of two or more metals (or a metal with non-metals) is called an alloy

An alloy is made by mixing metals.

It improves strength and durability.

Steel (iron and carbon), is an example of an alloy.

Explanation

Steel is most elastic among the rubber, steel, glass and sponge.

Steel having the most steep linear stress-strain curve among all.

A stiffer material will have a higher elastic modulus.

Explanation

Lithium is the lightest metal.

Density of 0.534 g/cm³.

It is an alkali metal,

The third element on the periodic table,

It is soft enough to be cut with a knife.

Uses: Due to its low density and high reactivity, it's used in aircraft and, famously, in the production of batteries for electric vehicles and consumer electronics. 

Explanation

The incorrect statement is: Metals are dull and soft.

Metals are typically:

• Solid at room temperature
• Have high melting and boiling points
• Good conductors of heat and electricity
• Shiny (although some metals may have a dull appearance due to oxidation or other surface treatments)
• Ductile (can be drawn into thin wires or sheets)
• Malleable (can be pounded into shape without breaking)

Explanation

Aluminum is the most abundant metal in the Earth's crust, and the third most abundant element therein, after oxygen and silicon.

MOST IMPORTANT KEY POINTS:

Most abundant elements found in air are? (1) Nitrogen (2) Oxygen (3) Argon

Most abundant elements found in earth’s crust are? (1) Oxygen (2) Silicon (3) Aluminum

Most abundant elements found in Universe are? (1) Hydrogen (2) Helium (3) Oxygen

Most abundant elements found in Human Body are? (1) Oxygen (2) Carbon (3) Hydrogen

Explanation

The penetration power of the X-rays depends  on the wavelength and frequency of X-rays

The penetration power of the X-rays will be more when the energy of the X-ray is more.

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Related Question:

Explanation

Silicon (Si) is the element most commonly used to fabricate solar cells and transistors.

Silicon is a semiconductor material that is widely used in the production of electronic components, including:

• Solar cells (photovoltaic cells)
• Transistors
• Microprocessors
• Diodes

Explanation

When the soap is in the form of micelles then it has the ability to clean the oily dirt which gets accumulated at the centre.

These micelles remain as colloidal solutions.

Therefore, the dirt from the cloth is easily washed away.