There are two ways to find the perimeter of a heart and a circle.
1. Theoretical(Mathematical) way
2. Practical way
In practical way, you can use a thread. Put the thread around the shape(heart or circle) completely. Then you can measure the thread using a scale. The measured length will be the perimeter.
Mathematically, we have a formula to find the perimeter of a circle(also called circumference).
Circumference=2*(pi)*r, where pi=22/7 and r=radius of the circle.
For perimeter of a heart, you will need to use the application of perimeter of a semicircle. The heart consists of 3 semi-circles. 2 semicircles are of same size, and third one is larger in size.