Explanation

• Sputnik 1 was launched by the Soviet Union on October 4, 1957.
• It from the Baikonur Cosmodrome in Kazakhstan, marking the beginning of the space age.
• The successful launch shocked the world and triggered the Space Race between the Soviet Union and the United States.

Explanation

• The unit of electric resistance is Ohms (Ω).
• Ohms measure the opposition to the flow of electric current.
• It represented by the symbol "R" in equations, such as R=V/I.

Explanation

• The principal axis is a horizontal line that passes through the centre of the lens, perpendicular to its surface.
• It is the central axis around which the lens is symmetrical.

Explanation

• A base is a substance that produces hydroxide ions (OH-) in an aqueous solution, making the solution basic.
• Examples of bases include sodium hydroxide (NaOH), calcium hydroxide (Ca(OH)2), and ammonium hydroxide (NH4OH).

Explanation

• Acid rain affects the photosynthesis and growth of plants.
• Acid rain can alter soil chemistry and damage leaves, which in turn negatively impacts the photosynthesis process and overall plant health.

Explanation

• Vaccines contain disease-producing pathogens (such as viruses or bacteria) in a weakened or attenuated form, or sometimes only a small portion of the pathogen (such as a protein or sugar).
• This allows the body to develop immunity against the pathogen without actually causing the disease.

Explanation

• Human insulin is inserted into bacteria, specifically E. coli, for the commercial preparation of insulin.
• This is done through genetic engineering, where the human insulin gene is cloned into a plasmid and then transformed into E. coli cells.
• The bacteria then produce human insulin, which can be harvested and used as a medication for diabetes.

Explanation

The Hypothalamus lies at the base of the thalamus and plays a crucial role in regulating various bodily functions, including:

• Body temperature
• Feelings of hunger and thirst
• Hormone secretion
• Sleep-wake cycles
• Emotional responses

Explanation

• To obtain a sharp image in a camera, the lens is moved back and forth to adjust the focus.
• It allowing the light rays to converge at the image sensor or film, resulting in a clear and sharp image.

Explanation

• Pressure increases when Area of contact is decreased.
• This is because the same force is concentrated on a smaller area, resulting in a higher pressure (P = F/A), similar to how a sharp object can exert more pressure than a blunt object.