$A$ boy walks uniformly along the sides of a rectangular park of size $400 \, m \times 300 \, m$,starting from one corner to the diagonally opposite corner. Which of the following statements is incorrect?

When are the path length and the magnitude of displacement the same?

When is an object said to be a particle?

The position of a particle along the $x$-axis at time $t$ is given by $x = 2 + t - 3t^2$. The displacement and the distance travelled in the interval $t = 0$ to $t = 1$ are respectively:

What is path length? What is displacement?

$A$ balloon is moving up in air vertically above a point $A$ on the ground. When it is at a height $h_{1}$,a girl standing at a distance $d$ (point $B$) from $A$ sees it at an angle $45^{\circ}$ with respect to the vertical. When the balloon climbs up a further height $h_{2}$,it is seen at an angle $60^{\circ}$ with respect to the vertical if the girl moves further by a distance $2.464d$ (point $C$). Then the height $h_{2}$ is (given $\tan 30^{\circ} = 0.5774$):