Question

An insect moves along the sides of a wall of dimensions 12 m x 5 m starting from one corner and reaches the diagonally opposite corner. If the insect takes 2 s for its motion then find the ratio of average speed to average velocity of insect.

• A. 17 : 13
• B. 27 : 13
• C. 17 : 16
  
• D. cant say
  

Answer 1

The correct option is A 17 : 13

$AB$ displacement, $t=2s$

And $(AC+BC)$ is the distance

$AB=\sqrt{5^2+{12}^2}=13m$

$v=\frac{13}{2}m/s$

Average distance$=12+5=17m$

Average speed$=\frac{17}{2}m/s$

Average speed:Average velocity$=\frac{\left(17/2\right)}{\left(13/2\right)}=\frac{17}{13}=17:13$