Question

A point mass is projected, making an acute angle with the horizontal. If angle between velocity $\overline{v}$ and acceleration $\overrightarrow{g}$ is $\theta$ at any time t during the motion, then $\theta$ is given by

• A. $0^{\circ }<\theta <{90}^{\circ }$
• B. $\theta ={90}^{\circ }$
• C. $\theta <{90}^{\circ }$
• D. $0^{\circ }<\theta <{180}^{\circ }$

Answer 1

The correct option is D $0^{\circ }<\theta <{180}^{\circ }$

Maximum angle between vectors is at initial projection $(\theta <{180}^{\circ })$
Minimum angle between vectors is at the final point of trajectory $(\theta >0^{\circ })$
Hence option D is correct.
For all other points $\theta$ will lie between $0^{\circ }$ and ${90}^{\circ }$