Free Measurements MCQs with Answers

131. In MKS system, the unit of pressure is:

• A. Dyne
• B. Atmosphere
• C. Pascal
• D. cm of Hg

Explanation: The Pascal (Pa) is the correct unit of pressure in the MKS system. It is defined as one Newton per square meter. Mathematically, pressure (P) is given by the formula: P=F/A, where F is force and A is area. In terms of units, 1 Pascal is equal to 1 Newton per square meter.

132. Orange light emitted from krypton-86 atoms was used to define:

• A. Kilogram
• B. Meter
• C. Centimetre
• D. Second

Explanation: The meter is defined in terms of the speed of light in a vacuum (c) and the duration of a specific number of oscillations of a cesium-133 atom. However, before the current definition, the meter was initially defined by a prototype physical object, the International Prototype of the Meter, and later by the wavelength of the orange light emitted by krypton-86 atoms. The current definition based on the speed of light was adopted to provide a more stable and precise standard.

133. The branch of physics which deals with motion of bodies under the action of forces is called:

• A. Mechanics
• B. Statistical Mechanics
• C. Thermodynamics
• D. Electrostatics

Explanation: Mechanics is the correct answer. It is the branch of physics that studies the motion of objects and the forces acting upon them. Classical mechanics, which deals with objects moving at speeds much less than the speed of light, includes both kinematics (the study of motion without regard to its causes) and dynamics (the study of the forces causing motion).

134. The branch of science which deals with properties of matter and energy is called:

• A. Chemistry
• B. Biology
• C. Geography
• D. Physics

Explanation: Physics is the correct answer. It is the branch of science that deals with the fundamental principles governing the behavior of matter and energy. Physics encompasses a wide range of topics, including mechanics, thermodynamics, electromagnetism, optics, and quantum mechanics, all of which explore the properties and interactions of matter and energy.

135. Physics is a quantitative science based primarily on:

• A. Fundamental Quantities
• B. Definition
• C. Experiment and Measurement
• D. Description of facts

Explanation: C is a correct statement. Physics relies heavily on experimental observations and measurements. Through experiments, physicists gather data to formulate and test theories. Measurements of physical quantities provide the quantitative basis for understanding and predicting the behavior of the physical world.

136. The Muslim scientist who wrote the books on Astronomy, Algebra and Arithmetic was:

• A. Ibn-al-Haitham
• B. Al-Beruni
• C. Al-Khawarizm
• D. Jabir bin Hayyan

Explanation: Al-Khawarizmi, often referred to as the "father of algebra," was a Persian mathematician, astronomer, and geographer who made significant contributions to the fields of algebra, arithmetic, and astronomy. His book "Al-Kitab al-Mukhtasar fi Hisab al-Jabr wal-Muqabala" (The Compendious Book on Calculation by Completion and Balancing) laid the foundations for algebra and introduced systematic methods for solving linear and quadratic equations.

137. Kilogram is the unit of:

• A. Mass
• B. Weight
• C. Volume
• D. Density

Explanation: Mass is a fundamental property of matter that measures the amount of substance in an object. The kilogram (kg) is the standard unit of mass in the International System of Units (SI).

138. Work is measured in Joules while energy is expressed in:

• A. Watt
• B. J.s
• C. J/s
• D. J

Explanation: The joule is the correct unit for energy. It measures the amount of work done or energy transferred when a force of one newton acts over a distance of one meter. It is the standard unit for both work and energy.

139. An example of fundamental quantity is:

• A. Area
• B. Volume
• C. Length
• D. Velocity

Explanation: Length is a fundamental quantity. It is a fundamental property of matter, and it is typically measured in meters (m) in the International System of Units (SI). Other quantities, such as area and volume, can be derived from length.

140. Ibn-al-Haitham developed:

• A. Mechanics
• B. Acoustics
• C. Relativity
• D. Optics

Explanation: Optics is the correct answer. Ibn al-Haitham made groundbreaking contributions to the field of optics. His most famous work, "Kitab al-Manazir" (Book of Optics), is a comprehensive study of light, vision, and optics. In this work, he discussed the nature of light, the formation of images, the anatomy of the eye, and the principles of reflection and refraction. Ibn al-Haitham's work laid the foundation for the understanding of optics in medieval Europe and had a profound influence on later scientists, including Roger Bacon and Johannes Kepler.