99-S1-Q11 Read more about 99-S1-Q11 Inverse square law, Krypton, starmaker, centre of mass. [STEP I 1999 Question 11 (Mechanics)]
92-S1-Q13 Read more about 92-S1-Q13 Inverse square law, comet, escape velocity. [STEP I 1992 Question 13 (Mechanics)]
