Explanation

The law of conservation of momentum states that the total momentum of a closed system (such as a system of two bodies) remains constant over time, as long as there are no external forces acting on the system.

This means that the total momentum before a collision is equal to the total momentum after the collision.

Explanation

Power is calculated as the rate of work done or energy transferred:

Power = Work / Time

= 20 J / 10 s

= 2 W

So, the machine's power output is 2 watts.

Explanation

• The shielding effect decreases across a period.
• This is because the increasing nuclear charge is not fully counterbalanced by the same number of inner electrons, resulting in a weaker shielding effect.

Explanation

The number of bioelements considered vital for life is 16. These essential elements include:

1. Carbon (C)
2. Hydrogen (H)
3. Oxygen (O)
4. Nitrogen (N)
5. Phosphorus (P)
6. Sulfur (S)
7. Potassium (K)
8. Calcium (Ca)
9. Magnesium (Mg)
10. Iron (Fe)
11. Sodium (Na)
12. Chlorine (Cl)
13. Copper (Cu)
14. Zinc (Zn)
15. Manganese (Mn)
16. Iodine (I)

Explanation

• Volvox is a genus of green algae that includes about 20 species of aquatic, photosynthetic organisms.
• They are characterized by their spherical or ellipsoidal shape and are typically found in freshwater environments.
• Volvox species are known for their unique colony structure, which consists of a hollow sphere of cells surrounding a central cavity.

Explanation

• Rana tigrina, also known as the Asian giant toad or the Indian bullfrog.
• It is a species of frog found in Southeast Asia and the Indian subcontinent.

Explanation

• In the human heart, blood returning from the lungs via the pulmonary veins drains into the left atrium.
• From there, it flows through the mitral valve into the left ventricle, which pumps it out to the rest of the body through the aorta.

Explanation

Acetic acid (CH3COOH) is a weak acid that only partially dissociates in water, forming a weak electrolyte solution.

It does not fully dissociate into ions like strong acids (like HCl) or strong bases (like KOH).

Explanation

• Paleontology is the scientific study of fossils and ancient life forms, focusing on the history of life on Earth, evolution, and extinction.
• Paleontologists use fossils to reconstruct the biology, ecology, and behavior of ancient organisms.

Explanation

Thalassemia is a genetic disorder that affects the production of hemoglobin, a protein in red blood cells that carries oxygen to the body's tissues.

It is characterized by abnormal hemoglobin production, leading to anemia, fatigue, and other complications.