If it requires 7.0 of work to stretch a particular spring by 2.1 from its equilibrium length, how much more work will be required to stretch it an additional 3.7?

Answer 1

I don't see any units in the problem statement. It is meaningless without them.

Answer 2

Sorry, inexcusable mistake. 7 Joules of work, 2.1 cm, and 3.7 cm