Units And Dimensions Question 5

Question 5 - 2024 (30 Jan Shift 2)

If mass is written as $m=kc^{P} G^{-1 / 2} h^{1 / 2}$ then the value of $P$ will be : (Constants have their usual meaning with $k$ a dimensionless constant)

(1) $1 / 2$

(2) $1 / 3$

(3) 2

(4) $-1 / 3$

Show Answer

Answer: (1)

Solution:

$m=kc^{P} G^{-1 / 2} h^{1 / 2}$

$M^{1} L^{0} T^{0}=\left[LT^{-1}\right]^{P}\left[M^{-1} L^{3} T^{-2}\right]^{-1 / 2}\left[ML^{2} T^{-1}\right]^{1 / 2}$

By comparing $P=1 / 2$