Test: Physical Quantities and Measurement - Class 6 MCQ

Cubit is a non-standard unit based on the length of the forearm, which varies from person to person, leading to inconsistencies in measurement compared to standard units like the metre or kilometre.

Area is measured in square metres (m²), which represents the size of a two-dimensional space. This unit allows for easy calculation of surfaces like floors or plots of land.

Mercury is opaque and shiny, making it easy to read against the graduated scale. Additionally, it does not wet the glass, which allows for accurate readings without the liquid clinging to the sides.

The upper fixed point of a thermometer generally represents the boiling point of water, which is 100°C (or 212°F). This point is crucial for calibrating the temperature scale used on the thermometer.

In the 24-hour clock system, 2:30 p.m. is expressed as 14:30. This format helps avoid confusion between morning and evening times.

The SI unit of mass is the kilogram (kg). This unit is widely used in scientific measurements and everyday applications to quantify mass.

Physical quantities help us compare and measure tangible items such as weight, length, and temperature, which are essential for making informed decisions in daily activities like shopping or healthcare.

Multiples and submultiples allow us to express measurements in larger or smaller units, respectively, such as using kilometres for large distances and millimetres for fine measurements, which facilitate easier comprehension and usage.

The names of SI units are always written in lowercase letters, even when named after scientists, with exceptions for symbols, which may be capitalized (e.g., N for Newton).

Parallax error occurs when the observer's eye is not directly aligned with the measurement mark, leading to inaccurate readings. This is particularly critical when using rulers or measuring instruments.

A measuring tape is flexible and can be used to measure both straight and curved lengths, making it ideal for longer distances compared to rigid instruments like rulers.

Force is a derived quantity, as it is obtained from the fundamental quantities of mass and acceleration (F = ma). Fundamental quantities include length, mass, time, temperature, electric current, luminous intensity, and amount of substance.

Volume is a derived quantity as it is calculated from fundamental quantities of length (e.g., volume = length × breadth × height), demonstrating how different fundamental measurements combine to form a new metric.

The correct relationship is that 60 seconds make up 1 minute. Understanding these relationships is fundamental for measuring time accurately and effectively in various contexts.

A clinical thermometer is typically placed under the tongue to measure body temperature accurately. This method ensures that the reading reflects the internal body temperature.

A beam balance is designed to compare the mass of an object against known standard weights, thus providing an accurate measure of the object's mass.

Handspan is a non-standard unit of measurement that varies between individuals, while CGS (centimetre-gram-second), MKS (metre-kilogram-second), and FPS (foot-pound-second) are established systems for standardized measurements.

The SI unit of temperature is Kelvin (K). While Celsius and Fahrenheit are commonly used, Kelvin is the standard unit in scientific contexts, particularly important in thermodynamics and physical sciences.

A laboratory thermometer is designed to measure a wider range of temperatures with greater precision, making it suitable for scientific experiments and laboratory settings.

The correct formula to convert Celsius to Fahrenheit is °F = (9/5 × °C) + 32. This formula means you multiply the Celsius temperature by 9, divide by 5, and then add 32 to get the Fahrenheit temperature. The formula is clearly given with both opening and closing brackets to avoid confusion, as recommended by the NCERT textbook for Class 6 (ICSE), Chapter: Physical Quantities and Measurement.