All Free Everyday Science MCQs with Answers

1631. Friction can be reduced by changing from _________?

• A. Rolling to sliding
• B. Sliding to rolling
• C. Dynamic to static
• D. Potential energy to kinetic energy

Explanation: Rolling friction is much smaller than sliding friction because the surfaces do not continually scrape past each other. This is why wheels, rollers and ball bearings make movement easier.

1632. "Father of Optics" is the title given to__________?

• A. Ibn-al-Haitham
• B. Ibn-e-Sina
• C. Al-Kandi
• D. Al-Biruni

Explanation: Ibn al-Haytham, known in the Latin West as Alhazen, is called the Father of Optics because he systematically studied vision, light and reflection. Ibn Sina and Al-Biruni are associated mainly with medicine and broader natural sciences, respectively.

1633. The light rays used for eliminating bacteria?

• A. X-rays
• B. infrared rays
• C. microwave radiation
• D. ultra-violet radiation

Explanation: Ultraviolet radiation damages the DNA of microorganisms and is therefore used to disinfect water, air and surfaces. X-rays can also kill cells at high doses, but UV is the standard radiation used for routine germicidal treatment.

1634. The Earth behaves like a magnet with ______ poles?

• A. Four
• B. Three
• C. Two
• D. None of these

Explanation: Earth’s magnetic field has two main magnetic poles, approximately near the geographic North and South Poles. These are magnetic poles, not four geographic or magnetic divisions.

1635. The Quantity of matter present in an object is its ________?

• A. Density
• B. Weight
• C. Mass
• D. None of these

Explanation: Mass measures the quantity of matter in an object and remains essentially the same wherever the object is located. Weight is the gravitational force on that mass, while density is mass per unit volume.

1636. Unit of force in (SI) is __________?

• A. Meter
• B. Newton
• C. Kilogram
• D. None of these

Explanation: The newton is the SI unit of force, equal to the force needed to give a 1-kilogram mass an acceleration of 1 metre per second squared. The metre measures length and the kilogram measures mass.

1637. Persistance of vision is the principle behind?

• A. Camera
• B. Spectroscope
• C. Cinema
• D. Periscope

Explanation: Cinema depends on persistence of vision, in which the eye briefly retains an image so rapidly projected frames appear as continuous motion. A camera records images but does not rely on this visual illusion for its basic operation.

1638. Gamma rays have greatest similarity with?

• A. a-rays
• B. X-rays
• C. b-rays
• D. U.V.-rays

Explanation: Gamma rays and X-rays are both high-frequency electromagnetic radiation and differ mainly in their source: gamma rays arise from atomic nuclei, while X-rays usually arise from electron processes. Alpha and beta rays are particles, so they are less similar to gamma rays.

1639. Change of state form liquid to solid is _________?

• A. Boiling
• B. Freezing
• C. Evaporation
• D. None of these

Explanation: Freezing is the change of state from liquid to solid, caused by removal of heat until the substance reaches its freezing point. Boiling and evaporation change a liquid into a gas.

1640. ________ it fills all the space avaliable.

• A. Liquid
• B. Gas
• C. Solid
• D. None of these

Explanation: A gas has neither a fixed shape nor a fixed volume, so it expands to occupy all the space available in its container. Liquids have a definite volume, while solids have both definite shape and volume.