Question

Force acting on a particle is given by $F=\frac{A - x}{B t}$ , where x is in metre and t is in seconds. The dimensions of B is -

• A. $MLT^{- 2}$
• B. $M^{- 1}T^{- 3}$
• C. $M^{- 1}T$
• D. $MT^{- 1}$

Answer 1

Answer: (C)

F = ma, we get
$F=\left[M^{1}\right] \, \left[\right.L^{1}T^{- 2}\left]\right.$
The dimension of force = $\left[\right.MLT^{- 2}\left]\right.$
$\left[F\right]=\frac{\left[A - x\right]}{\left[B\right] \left[t\right]}$
$\left[B\right]=\frac{\left[\right. L \left]\right.}{\left[M L T^{- 2}\right] \left[\right. T \left]\right.}=\left[M^{- 1} T^{1}\right]$