NTA Abhyas 2020
- Exam
- NTA Abhyas
- Year
- 2020
- Subject
- Physics
- Chapter
- Units and Dimensions
NTA Abhyas 2020 · Physics · Units and Dimensions
If velocity, force and time are taken as the fundamental...
If velocity, force and time are taken as the fundamental quantities, then using dimensional analysis choose the correct dimensional formula for mass among the following. is a dimensionless constant
Options
- A
- B
- C
- D
Correct answer
A.
Step-by-step solution
Let the quantity be Q, then,
Assuming that the function is the product of power functions of and ,
& &
where K is a dimensionless constant of proportionality. The above equation dimensionally becomes
i.e., , Now
Q = mass i.e.,
So Equation (ii) becomes
its dimensional correctness requires
and
which on solving yields
and
Substituting it in Equation (i), we get