All Free Everyday Science MCQs with Answers

1751. The average kinetic energy of the molecules of a body determines?

• A. heat
• B. temperature
• C. internal energy
• D. none

Explanation: Temperature measures the average kinetic energy of the random motion of particles, so faster average molecular motion means a higher temperature. Heat is energy transferred because of a temperature difference, not the energy a body simply possesses.

1752. Name the branch of science which deals with the study of sound and sound waves?

• A. Aeronautics
• B. Acoustics
• C. Aerostatics
• D. Aetiology

Explanation: Acoustics is the branch of physics concerned with sound, its production, transmission and effects. Aeronautics concerns aircraft, while aerostatics concerns gases at rest.

1753. The sounds of which frequency are human beings most sensitive?

• A. 400 hertz
• B. 20 hertz
• C. 20000 hertz
• D. 5000 hertz

Explanation: Human hearing is most sensitive roughly between 2,000 and 5,000 hertz, the range important for speech. Of the listed choices, 5,000 hertz is the best answer; 20 and 20,000 hertz are the approximate hearing limits.

1754. Who first measured the velocity of light?

• A. Einstein
• B. Newton
• C. Ole Roemer
• D. Galileo

Explanation: Ole Rømer made the first quantitative measurement of the speed of light in 1676 by observing delays in the eclipses of Jupiter's moon Io. Galileo attempted an experiment but could not measure the very high speed accurately.

1755. What is the range, in hertz, of the normal human hearing?

• A. 10 Hz to 10 kHz
• B. 20 Hz to 20 kHz
• C. 2000Hz
• D. 40 Hz to 40 kHz

Explanation: The normal approximate range of human hearing is 20 hertz to 20,000 hertz, or 20 kilohertz. Sensitivity and the upper limit decline with age, but this is the standard textbook range.

1756. Which liquid is used in an aneroid barometer?

• A. Mercury
• B. Alcohol
• C. Water
• D. None

Explanation: An aneroid barometer measures air pressure using a sealed, flexible metal capsule rather than a liquid column. Mercury barometers use liquid mercury, so “none” is correct here.

1757. Which lenses are used by people having short-sightedness?

• A. Convex
• B. Concave
• C. Concavo-convex
• D. Plain

Explanation: Short-sightedness, or myopia, focuses distant images in front of the retina. A concave lens spreads incoming rays slightly so the eye can focus them on the retina.

1758. Which type of motions are present in solid?

• A. translational
• B. rotational
• C. vibrational
• D. all of these

Explanation: Particles in a solid are held in fixed positions and can mainly vibrate about those positions. They do not freely translate through the solid as particles in a liquid or gas do.

1759. One Torr is equivalent to how many mm of Mercury?

• A. 1 mm
• B. 10 mm
• C. 100 mm
• D. 0.1 mm

Explanation: A torr is defined as one millimetre of mercury, so 1 torr equals 1 mmHg. It is a unit of pressure, not a length measurement in ordinary use.

1760. Sound travels_______ in solid materials then liquid?

• A. Constant
• B. Slowest
• C. Fastest
• D. None of these

Explanation: Sound generally travels fastest through solids because their closely packed particles transmit vibrations efficiently, and slowest through gases. Thus its speed in a solid is greater than in a liquid.