Problem: Sentence1: He spoke in a low key.
Sentence2: Some students cheated by using the answer key.
Q: Does the term key mean the same thing in both these sentences?

Answer: different meanings

Problem: Sentence1: The boulder came to rest just behind the house after rolling down the mountain.
Sentence2: A body will continue in a state of rest until acted upon.
Q: Does the term rest mean the same thing in both these sentences?

Answer: the same meaning

Problem: Sentence1: The alchemists tried to turn lead into gold.
Sentence2: Turn the heat down.
Q: Does the term turn mean the same thing in both these sentences?

Answer: different meanings

Problem: Sentence1: While there's life there's hope.
Sentence2: He gave up on life.
Q: Does the term life mean the same thing in both these sentences?

Answer:
the same meaning