A scientific probe of mass MprobeM_{\text{probe}}Mprobe is in a circular orbit around a dwarf planet. The gravitational attraction between them is F1 F_1\,F1 when their center-to-center separation is rrr. The probe releases a heavy lander, causing the probe's remaining mass to decrease by more than half of its original value (while remaining greater than zero). Simultaneously, the orbital separation of the remaining probe is halved.
If the new gravitational force on the remaining probe is F2F_2F2, which of the following correctly describes the relationship between F2 F_2\,F2 and F1F_1F1?
0<F2<2F10 < F_2 < 2 F_10<F2<2F1
0<F2<4F10 < F_2 < 4 F_10<F2<4F1
0<F2<0.125F10 < F_2 < 0.125 F_10<F2<0.125F1
0<F2<F10 < F_2 < F_10<F2<F1
31 exam-style questions on OCR A A Level Physics Gravitational fields, covering Point and spherical masses, Newton's law of gravitation, Planetary motion, and Gravitational potential and energy. Each one has a worked solution and a mark scheme showing where the marks go.