Question

Which of the following sets cannot enter into the list of fundamental quantities in any system of units?
(A) Length, mass and velocity
(B) Length, time and velocity
(C) Mass, time and velocity
(D) Length, time and mass

Answer 1

The quantities which define the laws of physics are termed as Physical quantities. They are of two types:

1. Fundamental quantities
2. Derived quantities

Complete step by step answer:
Fundamental quantities are not dependent on each other and can’t be further breakdown into other physical quantities. There are 7 fundamental quantities, the table below shows their name, units & symbols.

Sr. No.	Fundamental Quantities	Units	Symbols
1.	Length	Meter	m
2.	Mass	Kilogram	Kg
3.	Time	Second	s
4.	Electric current	Ampere	A
5.	Thermodynamic temperature	Kelvin	K
6.	Luminous intensity	Candela	Cd
7.	Amount of substance	Mole	Mol.

Now, on observing the options given in the question, we can identify that the correct answer is option (B). As velocity is the set dependent on length and time.

Note: Derived quantities are one which are dependent or derived from fundamental quantities.For example volume is dependent on fundamental quantity length. The units defined for the supplementary quantities specifically plane angle and solid angle are called the supplementary units. The rad is the unit for plane angle and the steradian is the unit for solid angle.