Everyday Science

The clock is the oldest invention among the options listed. Mechanical clocks date back to the 13th century, whereas the microscope was invented in the late 16th century, the barometer in the 17th century, and the bicycle in the 19th century.

Convex mirrors are used in anti-shoplifting devices because they provide a wider field of view, allowing shopkeepers to see a larger area and monitor for theft effectively.

Wooden doors absorb water during the rainy season through imbibition, causing the wood to swell and making the doors difficult to open or close. Imbibition is the process of absorption of water by solids causing them to swell.

The proton number, also known as the atomic number, is denoted by the symbol 'Z'. It represents the number of protons in the nucleus of an atom, which defines the element.

Hyetology is the branch of meteorology that studies rainfall and precipitation patterns. Therefore, the correct answer is 'Rainfall'.

Nylon is a synthetic polymer classified as a polyamide because it contains repeating amide groups (-CONH-) in its backbone. Rayon is a regenerated cellulose fiber, Terylene is a polyester, and Orion is an acrylic fiber, so they are not polyamides.

Radiology is the branch of medicine that uses X-rays and other imaging techniques to diagnose and treat diseases. The other options are unrelated fields.

Transistors do not require a warm-up period because they do not have a filament, unlike vacuum tubes which need their filaments to heat up before functioning properly.

Scientists identified Improtin-11 as a protein associated with the development and progression of colorectal cancer. Its discovery may help researchers better understand cancer growth and develop targeted treatments in the future.

Birth control pills contain synthetic hormones, such as estrogen and progestin, which help prevent ovulation and pregnancy. Sugars, vitamins, and minerals are not the active components in these pills.