2025 · Paper 1 · Physics
Question 8
The printed question, the official key, and each model’s JSON answer plus the reasoning it wrote.
Q08
Official 2

Model answers
Claude Fable 5.1
Anthropic
2
Claude Fable 5.1 reasoning
**Setting up the motion** The elevator's height is y = 8[1 + sin(2πt/T)], with T = 40π s. Angular frequency: ω = 2π/T = 2π/(40π) = 1/20 rad/s Acceleration of the elevator: a = d²y/dt² = −8ω² sin(ωt) Maximum magnitude of acceleration: a_max = 8ω² = 8 × (1/400) = 0.02 m/s² **Apparent weight** Apparent weight in the elevator = m(g + a), where a is the upward acceleration. - Maximum apparent weight: 50 × (10 + 0.02) = 501 N - Minimum apparent weight: 50 × (10 − 0.02) = 499 N **Maximum variation of weight observed** Variation = 501 − 499 = 2 N
GPT 6 Astra
OpenAI
2
GPT 6 Astra reasoning
No written reasoning was returned for this item.
GPT 5.6 Luna
OpenAI
2
GPT 5.6 Luna reasoning
No written reasoning was returned for this item.