An object is moving in a. Circle of radius of 5cm.calculate the distance and displacement 
1.when it  completes half the first  circle.
2.wben it completes one full circle.

Asked by ABHILASHA | 16th Apr, 2017, 10:01: AM

Expert Answer:

For reaching a solution we need to understand the difference in distance and displacement.
Distance is the length travelled r covered during the course of motion.
Whereas, the displacement is the actual change in position due to the same course of motion.


  1. When it completes half of the circle, the distance covered is half of the circumference of that circle that is, fraction numerator 2 πr over denominator 2 end fraction equals πr equals 15.71 space cm .
  2. When it completes one full circle, the distance covered is the measure of the circumference of the circle that is, 2 πr equals 31.42 space cm.


  1. When the moving object moves half of the circle, the change in the position is equal to the diameter of that circle and that is 5 cross times 2 equals 10 space cm
  2. When the same object moves one complete circle, then the object reaches back to the original position, therefore there is no change in the position. Therefore the displacement, in this case, is 0

Answered by Abhijeet Mishra | 17th Apr, 2017, 11:39: AM