Question

In $S=a+bt+c{t}^2$. S is measured in metres and t in seconds. The unit of c is:

• A. None
• B. m
• C. ms^-1
• D. ms^-2

Answer 1

The correct option is D ms^-2

$c{t}^2$ must have dimensions as $L$ because only quantities of the same dimensions can be added or subtracted. $\Rightarrow c$ must have dimensions as $\frac{L}{T^2}$
i.e.$L{T}^{-2}$ or $m{s}^{-2}$