All Free Everyday Science MCQs with Answers

1801. All of the following are electromagnetic radiations except__________?

• A. Red light
• B. Sound waves
• C. X-Rays
• D. Photon

Explanation: Red light and X-rays are electromagnetic waves, and photons are the quanta that carry electromagnetic radiation. Sound requires a material medium and is therefore mechanical, not electromagnetic.

1802. All of the following statements are incorrect except:

• A. Precision and accuracy should go side by side in a scientific work
• B. Scientific work must be precise, accuracy is not essential
• C. Scientific work must be accurate, precision is not essential
• D. Calculations must be made before any experiment

Explanation: Accuracy means closeness to the true value, while precision means repeatability; reliable scientific work requires both. Precision alone can give closely grouped but incorrect results.

1803. The average speed of a moving object during a given interval of time is always:

• A. the magnitude of its average velocity over the interval
• B. the distance covered during the time interval divided by the time interval
• C. one-half its speed at the end of the interval
• D. its acceleration multiplied by the time interval
• E. one-half its acceleration multiplied by the time interval

Explanation: Average speed is defined as the total distance travelled divided by the total time taken. It is not always equal to the magnitude of average velocity because an object may change direction.

1804. The SI base unit for mass is_____________?

• A. Gram
• B. Pound
• C. Kilogram
• D. Ounce

Explanation: The kilogram is the SI base unit of mass. Gram, pound and ounce are smaller or non-SI units used for measurement but are not the SI base unit.

1805. Which of the following is closest to a yard in length?

• A. 0.01m
• B. 0.1m
• C. 1m
• D. 10m
• E. 100m

Explanation: One yard equals 0.9144 metre, which is closest to 1 metre among the listed choices. The other values differ by factors of ten or more.

1806. The SI standard of time is based on_____________?

• A. the daily rotation of the earth
• B. the frequency of light emitted by Kr86
• C. the yearly revolution of the earth about the sun
• D. a precision pendulum clock
• E. none of these

Explanation: The SI second is defined using the frequency of radiation from the caesium-133 atom, specifically 9,192,631,770 cycles. Since no option mentions caesium-133, none of the listed statements is correct.

1807. Which is least Conductor of Electricity among the following?

• A. Wood
• B. Copper
• C. Iron
• D. Water

Explanation: Dry wood has very high electrical resistance because it contains few freely moving charge carriers. Copper and iron conduct well, while ordinary water conducts to some extent because of dissolved ions.

1808. Sunlight is composed of___________?

• A. Three colours
• B. six colours
• C. seven colours
• D. eight colours

Explanation: Visible sunlight is traditionally described as seven colours: red, orange, yellow, green, blue, indigo and violet. A prism separates these colours because each wavelength bends by a different amount.

1809. At what angle above the horizon must the sun be to create a rainbow?

• A. 90 degrees
• B. 60 degrees
• C. 40 degrees
• D. 65 degrees

Explanation: A primary rainbow is normally visible when the Sun is below about 42 degrees above the horizon, making 40 degrees the closest option. At higher solar angles, the rainbow is difficult or impossible to see from level ground.

1810. Short-sight defect could be corrected by a _____________ lens?

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

Explanation: Myopia makes distant objects focus in front of the retina, so a concave lens spreads incoming rays and shifts the focus back onto the retina. A convex lens is used for long-sightedness.