Explanation

• Solar energy uses sunlight directly to generate electricity.
• It works through solar panels (photovoltaic cells).
• Sunlight is converted into electrical energy.
• It is a clean and renewable energy source.

Last verified on 24-05-2026

Explanation

• Mitochondria are known as the “powerhouse of the cell.”
• They produce energy in the form of ATP.
• This energy is used for all cellular activities.
• Found in almost all eukaryotic cells.

Last verified on 24-05-2026

Explanation

• Fats are essential nutrients that store energy in the body.
• They help in maintaining body temperature by providing insulation.
• Fat layer under skin reduces heat loss.
• They also protect internal organs from shock.

Last verified on 24-05-2026

Explanation

• Laser produces a highly concentrated beam of light.
• Its high intensity allows it to focus large energy on a small area.
• This concentrated energy can melt or vaporize materials.
• That is why lasers are used in cutting and industrial processing.

Last verified on 24-05-2026

Explanation

• Isobars are atoms of different elements with the same mass number.
• They have different atomic numbers (protons).
• They represent different chemical elements but equal total nucleons.
• The concept of isobars was introduced in nuclear chemistry.
• It studies by Alfred Walter Stewart.
• Also later refined by Frederick Soddy.

Last verified on 24-05-2026

Explanation

• Radioactive substances emit three main types of radiation: alpha, beta, and gamma.
• Alpha radiation is made up of helium nuclei (2 protons + 2 neutrons).
• It is positively charged.
• It has low penetration power.
• It is the heaviest and slowest type of nuclear radiation.

Last verified on 24-05-2026

Explanation

• Electrons are negatively charged particles outside the nucleus.
• They move in energy levels (shells) around the nucleus.
• Chemical bonding occurs due to sharing or transfer of electrons.
• Protons and neutrons remain inside the nucleus.

Last verified on 24-05-2026

Explanation

• Thermal power plants generate electricity using heat energy.
• Fuel combustion (coal, gas, oil) produces heat.
• This heat is used to produce steam that drives turbines.
• Turbines convert mechanical energy into electrical energy.

Last verified on 24-05-2026

Explanation

The energy of a photon is calculated using the formula E = hf, where:

• h = Planck’s constant
• f = frequency of the photon

This shows that photon energy is directly proportional to its frequency.

Last verified on 23-05-2026

Explanation

• When frequency is above the threshold, electrons are emitted from the metal surface.
• Increasing intensity means more photons fall on the surface, so more electrons are emitted.

Last verified on 23-05-2026