Explanation

Nuclear energy is the energy released from the nucleus of an atom, either through fission (splitting of atoms) or fusion (combination of atoms).

This energy is released in the form of heat and radiation, and is harnessed in nuclear power plants to generate electricity.

Key Points:

• Solar energy is energy from the sun
• Geothermal energy is energy from the Earth's internal heat
• Tidal energy is energy from ocean tides

Explanation

The kinetic energy (K.E) of an object is calculated as:

• K.E = (1/2) x mass x velocity^2
• = (1/2) x 1 kg x (1 m/s)^2
• = 0.5 Joule
• = 1/2 Joule

So, the kinetic energy of the body is 1/2 Joule or 0.5 Joule.

Explanation

A communication satellite in a geostationary orbit completes one revolution around the Earth in 24 hours.

This is the same amount of time it takes the Earth to rotate once on its axis.

Explanation

• When the pressure on a gas increases, the molecules are forced closer together, resulting in a higher density.
• This is because the volume of the gas decreases as the pressure increases, causing the molecules to be more concentrated.

Explanation

• Magnesium (Mg) is an alkaline earth metal that loses two electrons from its outer shell to form a divalent cation (Mg²⁺).
• This means that it typically loses two electrons to form compounds, resulting in a valency of +2.

Explanation

• Atomic radius decreases along a period as you move from left to right.
• This is because the number of protons in the nucleus increases, which pulls the electrons closer to the nucleus, resulting in a smaller atomic radius.

Explanation

The secondary cell wall, found in plant cells, is primarily composed of:

• Cellulose (a polysaccharide, the main component of plant cell walls)
• Lignin (a complex organic compound that provides strength and rigidity)

Explanation

Fermentation is an anaerobic process in which microorganisms like yeast and bacteria break down food components into other products .

This gives fermented foods their unique and desirable taste, aroma, texture and appearance.

Explanation

• In the periodic table, a rows is considered to be a periods.
• Periods are the horizontal rows of elements in the periodic table.

Explanation

One mole of glucose (180g) produces a maximum of 2827 kJ (kilojoules) of energy through cellular respiration.

This energy is released as ATP (adenosine triphosphate) and is used to power various cellular activities.