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The maximum and minimum distances of a comet from the Sun are 1.6×10¹² m and 8.0×10¹⁰ m respectively. If the speed of the comet at the nearest point is 6×10⁴ m s⁻¹, the speed at the farthest point is

Asked in JEE Main 16th March 1st Shift 2021 · Second law and areal velocity

• (1) 3.0×10³ m s⁻¹
• (2) 4.5×10³ m s⁻¹
• (3) 1.5×10³ m s⁻¹
• (4) 6.0×10³ m s⁻¹

Step-by-step solution

Why the other options are wrong

• (2) No ratio of the two given distances produces this; it is a near miss placed beside the correct value.
• (3) Half the correct answer, which is what you get by halving the near distance, for instance by reading 8.0×10¹⁰ m as a semi-axis rather than the actual nearest distance.
• (4) Results from rounding the distance ratio to 1/(10) instead of computing (8.0×10¹⁰)/(1.6×10¹²)=1/(20).

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