Question

$S^2={at}^4$

Here $S$ is measured in metres, $t$ in second. Then the unit of $a$ is:

• A. $m^2{s}^4$
• B. $m^2{s}^{-4}$
• C. ${ms}^2$
• D. ${ms}^{-2}$

Answer 1

The correct option is B $m^2{s}^{-4}$

$S^2=a{t}^4$
$M^0{L}^2{T}^0=a\left(M^0{L}^0{T}^4\right)$
$a=M^0{L}^2{T}^{-4}$
$\Rightarrow a=m^2{s}^{-4}$