Question

A body moves along the sides of an equilateral triangle of side 20 cm and comes back to the initial point after one round. Then the distance and displacement of the body respectively are

• A. 60 cm, 0 cm
• B. 60 cm, 20 cm
• C. 20 cm, 60 cm
• D. 20 cm, 0 cm

Hint:

Distance is the total path length, while displacement is the straight-line distance between the starting and ending points. In a closed path, the displacement is always zero.

Answer 1

The Correct Option is A

Let the side of the equilateral triangle be \( 20 \, \text{cm} \). - The distance covered by the body is the total length of the path travelled. Since the body moves along all three sides of the triangle and returns to the starting point, the total distance is the perimeter of the triangle: \[ \text{Distance} = 3 \times 20 = 60 \, \text{cm} \] - The displacement of the body is the straight-line distance from the starting point to the ending point. Since the body returns to the same point after completing the triangle, the displacement is zero: \[ \text{Displacement} = 0 \, \text{cm} \] Thus, the distance is \( 60 \, \text{cm} \) and the displacement is \( 0 \, \text{cm} \). The correct answer is (A).