Question

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

• A. He has travelled a distance of 700 m
• B. His displacement is 700 m
• C. His displacement is 500 m
• D. His velocity is not uniform throughout the walk

Answer 1

Step 1: Given

Dimension of park = 400 m × 300 m

Step 2: Formula used

Perpendicular² + Base² = Hypotenuse²

Step 3: Finding Displacement

Displacement $\overrightarrow{AC}$ = $\overrightarrow{AB}$ + $\overrightarrow{BC}$
AC = $\sqrt{{\left(AB\right)}^2+{\left(BC\right)}^2}$ = $\sqrt{{\left(400\right)}^2+{\left(300\right)}^2}$ = 500m

Step 3: Finding total distance
Total distance = AB + BC = 400 + 300 = 700m.

As the boy walks from AB to BC his direction of motion changes, hence his velocity is not uniform.

Hence, the correct option is B (His displacement is 700).