Question

A body is accelerating in a straight line. The unbalanced torte acts

• A. in the direction of motion of the body
• B. in a direction opposite to the direction of motion
• C. in a direction perpendicular to the direction of motion of the body
• D. none of these

Answer 1

Answer: (C)

in a direction perpendicular to the direction of motion of the body

$\begin{array}{c}\text{Given - Body accelerating in Straight line.}\\ \text{we know that}\overrightarrow{\tau }\text{torgue vector}\\ \begin{array}{c}\overrightarrow{\tau }=\overrightarrow{r}\times \overrightarrow{F}\overrightarrow{r}=\text{radial vector}\\ \overrightarrow{F}=\text{Foru vector}\end{array}\\ \Rightarrow \overrightarrow{\tau }=m\cdot (\overrightarrow{r}\times \overrightarrow{a})\\ \Rightarrow \text{For a particular radial vector we get}\\ \text{the}\overrightarrow{\tau }\perp \overrightarrow{a}\text{by the cross product}\\ \Rightarrow \text{Option}\left(c\right)\text{is correct.}\end{array}$