Q. A bird files for 4s with a velocity of $|t - 2|ms^{- 1}$ in a straight line, where $t =$time in second. It covers a distance of
A) 8 m
B) 6 m
C) 4 m
D) 2 m
Explanation
(c) Since, $v = (t - 2),$ so $v \propto t$. On plotting a graph between $v$ and $t$ we get a straight line $AB$ and $BC$ as shown in figure. The distance covered in 4$s$ is equal to the area under the velocity-time graph = Area of $\mathrm{\Delta}OAB$ $\mp$Area of $\mathrm{\Delta}BCD$
$= \frac{2 \times 2}{2} + \frac{2 \times 2}{2} = 2 + 2 = 4$m
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.