Free Physics in Daily Life MCQs with Answers

91. What measurement scale is used to determine wind speed?

• A. Richter Scale
• B. Beaufort Scale
• C. Meter-second scale
• D. None of these

Explanation: The Beaufort scale classifies wind force by observing its effects, ranging from calm conditions to hurricane-force winds. The Richter scale measures earthquake magnitude, not wind.

92. Which diagnostic scan gives some of the highest radiation doses in diagnostic radiography ?

• A. CT-Scan
• B. Ultrasound
• C. MRI
• D. X-Ray

Explanation: CT scans use many X-ray exposures to create cross-sectional images, so they generally deliver more radiation than a routine X-ray. Ultrasound and MRI use no ionising radiation.

93. Velometer is used to measure?

• A. Rain
• B. Speed of Air
• C. Wind pressure
• D. Heat

Explanation: A velometer, or anemometer-type instrument, measures the speed of moving air or wind. It does not directly measure rainfall, heat, or wind pressure.

94. The spray bottles used as window or household cleaner or perfume spray works on: __________?

• A. Capillary action
• B. Bernoulli's Principle
• C. Pascal's Law
• D. Stoke's Law

Explanation: In a spray bottle, rapidly moving air lowers pressure above the liquid, allowing atmospheric pressure to push the liquid up the tube and disperse it. This is an application of Bernoulli's principle.

95. What is unit of Pressure?

• A. Barr
• B. Torr
• C. Pascal
• D. All of these

Explanation: The pascal is the SI unit of pressure, while the torr and bar are also accepted pressure units. Thus, “Barr” is presumably a misspelling of bar, making all the listed units valid.

96. Triple point of water is _________?

• A. 271 K
• B. 272.2 K
• C. 273.16 K
• D. None of these

Explanation: Water’s triple point, where ice, liquid water and water vapour coexist in equilibrium, is defined as 273.16 K. This is slightly above the ordinary ice point of about 273.15 K.

97. Stars in the sky appear to twinkle due to _________?

• A. a series of refractions
• B. a series of reflections
• C. a surface tension phenomenon
• D. multiple diminishing brightness

Explanation: Starlight passes through turbulent layers of Earth’s atmosphere, where repeated refraction changes its apparent direction and brightness. Nearby planets usually twinkle less because their visible discs average out these fluctuations.

98. A bird sitting on a high tension electric wire does not get electrocuted because:

• A. Sit has high resistance
• B. the body is earthed
• C. it does not form a closed path for the flow of current
• D. its feet are good insulators

Explanation: A bird on a single wire has both feet nearly at the same electrical potential, so there is no significant voltage across its body to drive current. Merely touching a high-voltage wire is dangerous when another contact provides a potential difference.

99. 1 tonne = _____ kg?

• A. 100
• B. 400
• C. 1000
• D. 4000

Explanation: A tonne, also called a metric ton, is equal to 1,000 kilograms. This is distinct from some historical or regional ton units, whose masses differ slightly.

100. A photostat machine works on _____________?

• A. electromagnetic image making
• B. magnetic image making
• C. thermal image making
• D. electrostatic image making

Explanation: A photostat machine gives the document and drum electrostatic charges, so toner sticks selectively to form the copy. This is why its basic principle is called electrostatic image making.