No they are not the same material because having the same density doesnt mean its the same material also they can have a different density and be the same material
So when making structures you have to have squares rectangles right and a triangle and another triangle equals a square so thats all there is to it
Meters Micrometers centimeters millimeters
Your potential energy and mass don't tell what your weight is.
If I walk up from the first floor to the second floor, my weight hasn't
changed even though my potential energy has increased.