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qid 9451 · physics

Question: A steel ball of velocity $5 \mathrm{~m} / \mathrm{s}$ strikes a smooth, heavy steel plate at an angle of $30^{\circ}$ from the normal. If the coefficient of restitution is 0.8 , at what velocity does the steel ball bounce off the plate?

  1. $4.8$$\mathrm{~m} / \mathrm{s}$
  2. $3.8 \mathrm{~m} / \mathrm{s}$
  3. $4.3$$\mathrm{~m} / \mathrm{s}$
  4. $4.0 \mathrm{~m} / \mathrm{s}$
  5. $3.5$$\mathrm{~m} / \mathrm{s}$
  6. $4.6 \mathrm{~m} / \mathrm{s}$
  7. $2.5 \mathrm{~m} / \mathrm{s}$
  8. $5.0$$\mathrm{~m} / \mathrm{s}$
  9. $3.2 \mathrm{~m} / \mathrm{s}$
  10. $2.8 \mathrm{~m} / \mathrm{s}$

Our answer: C. $4.3$$\mathrm{~m} / \mathrm{s}$ Source quote machine-checked (exact quote)

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How it was answered

Multi-step solver (maze), replayed by code

card: maze · card sha256 b3d276a00628cd7e…

Current source

Wikipedia, Coefficient of restitution

https://en.wikipedia.org/wiki/Coefficient_of_restitution

“The coefficient of restitution can be thought of as a measure of the extent to which energy is conserved when an object bounces off a surface.”

Source quote machine-checked (exact quote)

retrieved 2026-09-18T00:33:50.932Z

page text sha256 cca5a9256be2d24d… · content sha256 6766d4812642b894…

addendum maze_qid9451_b4_maze_input_ADDENDUM_source_rs20260918T003350Z · sha256 e4d6454159c2ed95… · replaces the version below, addendum sha256 f4db9a42304a5fe7…

Earlier version (superseded)

https://en.wikipedia.org/wiki/Coefficient_of_restitution

Source weak (http_get_200_text_and_question_terms)

retrieved 2026-09-17T23:25:05.794Z

page text sha256 237122f5fc423ec7… · content sha256

addendum maze_qid9451_b4_maze_input_ADDENDUM_source_bf20260917T232505Z · sha256 f4db9a42304a5fe7… · replaces the version below, addendum sha256 6f99f16eacddc2d9…

Earlier version (superseded)

No public source has been found for this card yet (3 places checked internally).

addendum maze_qid9451_b4_maze_input_ADDENDUM_source · sha256 6f99f16eacddc2d9…

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