151.9j
Explanation:
PE=1/2kx^2
PE=1/2(980)(.50)= 245j
PE=(1/2)(980)(.81)= 396.9j
396.9- 245= 151.9j
1 is b because a runs 20 and b rus 102 is c
Answer/ Explanation
the loop has no force and the wires cancel each other but the wire on the loop has a force
The segment a get the same force for both but in the loop segment b get an opposite force so the net force on the loop is smaller
The loop wire has forces that all cancel out while the other straight wire doesn't.
I would need an example or photo to give an answer.