Question

1. I'll break the window. [contracted form]

2. I will break the window. [no accent on 'will']
3. I will break the window. [accent on 'will']
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Is #2 stronger than #1 in meaning?
Is #3 stronger than # 2 in meaning? Is #3 the strongest of the three in meaning?

Answer 1

1 and 2 mean the same thing. 3 has the emphasis, yes, and indicates the speaker believes no one can stop him/her.