Free Physics in Daily Life MCQs with Answers

291. It is observed that the total pressure exerted by air on the man of average size is around 14.7 lb wt. per square inch. But the man feels quite comfortable,. It is because of__________?

• A. An equal and opposite pressure acts from inside
• B. of the height of a man
• C. of gravity
• D. Earth pulls the man upward
• E. None of these

Explanation: Atmospheric pressure is balanced by pressure from fluids and gases inside the body acting outward, so the net force on the body is small. The pressure is not absent; it is balanced internally.

292. Pressure is measured by_________?

• A. barometer
• B. Voltmeter
• C. Lactometer
• D. Ammeter

Explanation: A barometer measures atmospheric pressure, commonly using a column of mercury or a pressure-sensitive aneroid mechanism. A voltmeter measures voltage, an ammeter current, and a lactometer the relative density of milk.

293. Echo is a ___________ of sound?

• A. Reflection
• B. Refraction
• C. Interference
• D. None

Explanation: An echo occurs when a sound wave reflects from a distant surface and returns to the listener after a noticeable delay. Refraction changes the direction of a wave as it enters another medium, whereas an echo specifically involves reflection.

294. Which stone floats on water?

• A. Pumice stone
• B. Lime stone
• C. Basalt stone
• D. Quartzite stone

Explanation: Pumice contains many trapped air spaces, making its average density lower than that of water, so it can float. The other listed rocks are generally denser than water.

295. The scientific study of measurement is known as __________?

• A. Entomology
• B. Metrology
• C. Ichthyology
• D. Ecology

Explanation: Metrology is the science of measurement, covering units, standards, calibration and measurement accuracy. The other terms name biological or environmental fields.

296. How many meters are in one mile?

• A. How many meters in one mile?
• B. 1409.34
• C. 1509.34
• D. 1609.34
• E. None of Above

Explanation: One international mile equals exactly 1,609.344 metres, commonly rounded to 1,609.34 metres. Option a repeats the question instead of giving a measurement.

297. kilohertz (kHz) is a unit which measures?

• A. Power used by a current of one ampere
• B. Electromagnetic radio wave frequencies
• C. Voltage
• D. Electric resistance

Explanation: A kilohertz equals 1,000 hertz and measures frequency, including the frequency of electromagnetic radio waves. Voltage, resistance and power use volts, ohms and watts respectively.

298. One Joule is equal to__________?

• A. 105 ergs
• B. 103 ergs
• C. 107 ergs
• D. 1011 ergs

Explanation: One joule equals one kilogram metre squared per second squared, while one erg is the CGS equivalent of 10⁻⁷ joule. Hence, 1 joule equals 10⁷ ergs.

299. 'Bar' is the unit of___________?

• A. Temperature
• B. Heat
• C. Atmospheric pressure
• D. Current

Explanation: The bar is a unit of pressure, commonly used for atmospheric and gas pressure; 1 bar is close to normal atmospheric pressure. Temperature, heat and electric current use different units.

300. How many Dynes are there in one gram weight?

• A. 993
• B. 981
• C. 250
• D. 375

Explanation: In the CGS system, the weight of a 1-gram mass is its mass multiplied by gravitational acceleration, about 981 cm/s². Thus, one gram-weight is approximately 981 dynes.