Free Physics in Daily Life MCQs with Answers

61. Instrument used for measuring very high temperature is __________?

• A. Pyroscope
• B. Pyrometer
• C. Seismograph
• D. Xylometer

Explanation: A pyrometer measures very high temperatures, often without touching the hot object by detecting its emitted radiation. A seismograph records earthquakes, while a xylometer measures the volume of wood.

62. 1 nanometer = ?

• A. 10-3 meter
• B. 10-6 meter
• C. 10-9 meter
• D. 10-12 meter

Explanation: The prefix nano means one-billionth, or 10⁻⁹, of a unit. Thus, one nanometre equals 10⁻⁹ metre.

63. When white light is passed through a prism, it splits into __________ colours.

• A. 5
• B. 6
• C. 7
• D. 8

Explanation: A prism disperses white light into the seven visible spectral colours, commonly remembered as VIBGYOR: violet, indigo, blue, green, yellow, orange and red.

64. Which from the following is true for "Sound"?

• A. Sound cannot travel through a vacuum
• B. Sound cannot travel through gases
• C. Sound cannot travel through liquids
• D. Sound cannot travel through solids

Explanation: Sound is a mechanical wave, so it needs particles of a medium to carry its vibrations and cannot travel through a vacuum. It can travel through gases, liquids and solids.

65. A camera uses a __________ to form an image.

• A. convex lens
• B. concave lens
• C. condenser lens
• D. none of these

Explanation: A camera uses a converging convex lens to focus reflected light and form a real image on its film or electronic sensor. A concave lens diverges light and cannot normally form this image by itself.

66. The SI unit of "pressure" is _________.

• A. pascal
• B. joule
• C. tesla
• D. henry

Explanation: The pascal is the SI unit of pressure and equals one newton per square metre. Joule measures energy, tesla measures magnetic flux density, and henry measures inductance.

67. Radioactivity was discovered by __________?

• A. Kelvin
• B. Thomson
• C. Rutherford
• D. Bacquerel

Explanation: Henri Becquerel discovered radioactivity in 1896 while investigating uranium salts. Rutherford later studied the nature of radioactive emissions, but he was not the discoverer of radioactivity.

68. For a fixed mass of gass at constant temperature, if we decrease volume, the pressure will _________?

• A. also decrease
• B. increase
• C. remains constant
• D. none of these

Explanation: Boyle’s law states that pressure is inversely proportional to volume at constant temperature, so reducing the volume increases the pressure. This applies to a fixed amount of gas.

69. 'Magnetometer' is used to measure: ______________?

• A. Air Pressure on Ships
• B. Electromagnetic Force in Space Devices
• C. Changes in the Earth's Magnetic Field
• D. Changes in Oceanic Current

Explanation: A magnetometer detects the strength and direction of magnetic fields, including changes in Earth’s magnetic field. It is not primarily an instrument for measuring air pressure or ocean currents.

70. Which one of the following of glass can cut ultraviolet rays?

• A. Jena Glass
• B. Soda Glass
• C. Pyrex Glass
• D. Crookes Glass

Explanation: Crookes glass contains compounds that strongly absorb ultraviolet radiation and was used in protective eyewear. Ordinary soda glass transmits or only partly absorbs some ultraviolet wavelengths rather than providing this specialized cutoff.