AS Daily A Level Physics question
Two identical light springs support the same weight. In arrangement 1, the springs are in parallel (both attached to the support and the weight). In arrangement 2, the same two springs are connected in series (end-to-end). The springs remain within their elastic limit. Which statement about the total extension when changing from arrangement 1 to arrangement 2 is correct?
Answer
The correct answer is A.
Correct: A — It becomes four times larger. B assumes the stiffness only halves when going from parallel to series, but it actually drops by a factor of four (from 2k to k/2), so twice is too small. C ignores that configuration affects overall stiffness, so the extension cannot stay the same. D reverses the effect, as series makes the system less stiff, not stiffer, so the extension increases rather than halves.