Explanation

• Gamma rays have the highest penetrating power among these particles.
• Due to their lack of mass and charge.
• It allowing them to pass through most materials.

Last verified on 12-04-2026

Explanation

• Celsius and Fahrenheit are two temperature scales.
• At one special point, both scales show the same value.
• This happens when temperature is −40.
• So, −40°C = −40°F.

Last verified on 11-04-2026

Explanation

• Energy due to motion is called kinetic energy.
• Any moving object possesses this energy.
• It depends on mass and velocity of the body.
• Faster motion means more kinetic energy.

Last verified on 11-04-2026

Explanation

• Rutherford’s gold foil experiment (1911) showed that an atom has a small, dense, positively charged center called the nucleus.
• The mass of the atom is concentrated in the nucleus, while most of the atom is empty space.

Additional information:

• Nucleus contains: Protons (+) and neutrons (neutral)
• Electrons move around the nucleus in mostly empty space
• The experiment involved alpha particles being deflected by the nucleus.

Last verified on 10-02-2026

Explanation

• Solids → fastest sound speed
• Liquids → medium speed
• Gases → slowest speed

Steel is more elastic and dense.

• Steel ≈ 5000 m/s
• Air ≈ 332 m/s
• Water ≈ 1500 m/s

Last verified on 11-04-2026

Explanation

• Enzymes sometimes need a non-protein component to function properly.
• This non-protein part is called a cofactor.
• If it is loosely attached, it can easily separate from the enzyme.
• Cofactors help enzymes carry out biochemical reactions.
• They may be inorganic ions or organic molecules.

Last verified on 10-04-2026

Explanation

Explanation

• Chronometer is a highly precise time-measuring instrument.
• It is often used in navigation and scientific experiments.
• It is designed to measure time accurately, even under varying conditions.
• Chronometers played a key role in determining longitude at sea.

Last verified on 03-04-2026

Explanation

• Polio Vaccines: Developed to prevent poliomyelitis, a viral disease causing paralysis.
• Jonas Salk (US, 1950s): Created the first inactivated (killed) polio vaccine; tested on himself and family in 1953; officially used in 1955.
• Albert Sabin (1961): Developed the live attenuated (weakened) oral polio vaccine.
• Recent Campaigns: Israel launched a polio vaccine drive in April 2022 after 1988 efforts.

Last verified on 03-04-2026

Explanation

• Seismology is the study of earthquakes and seismic waves that move through and around the Earth.
• A seismologist is a scientist who studies earthquakes and seismic waves.

Last verified on 03-04-2026