All Free Everyday Science MCQs with Answers

1701. Which of the following is a force?

• A. Heat
• B. Light
• C. Magnetism
• D. Kinetic

Explanation: Magnetism produces forces of attraction and repulsion, so it is treated as a force-producing physical interaction. Heat and light are forms of energy, while kinetic energy is energy due to motion.

1702. Dioptre is a unit of measurement for __________ ?

• A. Current
• B. Lens
• C. Force
• D. Focal Length

Explanation: A dioptre is the unit of optical power of a lens, equal to the reciprocal of its focal length in metres. Thus a lens with a focal length of 0.5 metre has a power of 2 dioptres.

1703. Eletromagneticism is the branch of___________?

• A. Chemistry
• B. Physics
• C. Both
• D. None of these

Explanation: Electromagnetism is a branch of physics that studies electric charges, electric fields, magnetic fields, and their interaction. Chemistry may use these principles but is not the branch that defines them.

1704. Sound travels in air at an average speed of nearly________ ?

• A. 1257 miles per hour
• B. 755 miles per hour
• C. 330 miles per hour
• D. None of these

Explanation: Sound travels through air at about 343 metres per second, which is roughly 767 miles per hour under ordinary conditions. Therefore 755 miles per hour is the closest option.

1705. When sound waves travel from air to water which of the following quantities remains unchanged?

• A. Speed
• B. Frequency
• C. Intensity
• D. Wavelength

Explanation: The frequency of a wave is fixed by its source and does not change when sound enters another medium. Its speed and wavelength change according to the new medium, and intensity may also change.

1706. Which instrument is used to measure the power of electric circuit ?

• A. Wavemeter
• B. Viscometer
• C. Wattmeter
• D. None of these

Explanation: A wattmeter measures electrical power directly in watts by combining measurements of voltage and current. A wavemeter measures wavelength, while a viscometer measures fluid viscosity.

1707. Tyndall effect is related to the ______ of light?

• A. Reflection
• B. Dispersion
• C. Scattering
• D. Refraction

Explanation: The Tyndall effect is the visible scattering of light by colloidal particles, as seen when a beam passes through dusty air or mist. Reflection, refraction and dispersion are different optical effects.

1708. ______ is the "Work done in moving a unit charge between two points in an electric circuit"?

• A. Potential difference
• B. Current
• C. Power
• D. Resistence

Explanation: Potential difference is the work done per unit charge in moving charge between two points, expressed as V = W/Q. Current measures charge flow per unit time, while power measures the rate of doing electrical work.

1709. The most suitable unit for expressing nuclear radius is_______?

• A. Angstrom
• B. Micro
• C. Nano meter
• D. Fermi

Explanation: A fermi, equal to 10^-15 metre, is suitable for nuclear dimensions because atomic nuclei are only a few femtometres across. Angstroms and nanometres are more appropriate for atomic and molecular scales.

1710. Name the Scientist who stated that matter can be converted into energy?

• A. Boyle
• B. Einstein
• C. Avogadro
• D. Lavoisier

Explanation: Einstein established the mass-energy equivalence expressed by E = mc², showing that mass can be converted into energy and vice versa. Boyle and Lavoisier made important chemical contributions but did not state this relation.