EXPLANATION
Question: Which of the following is a fundamental dimension?
- a) Ampere
- b) Kelvin
- c) Mole
- d) Second
ANSWER: d) Second
EXPLANATION:
The correct answer is d) Second. The second (s) is a fundamental dimension in the International System of Units (SI). It is the base unit of time and is considered a fundamental dimension because other derived units, such as velocity (m/s), acceleration (m/s²), and frequency (1/s or Hz), are defined in terms of the second.
On the other hand, the ampere (A), kelvin (K), and mole (mol) are not considered fundamental dimensions. The ampere is the unit of electric current, the kelvin is the unit of temperature, and the mole is the unit of amount of substance. These units are derived from combinations of fundamental dimensions such as time, length, mass, and others.
