everyday science MCQ #1667

Who was the first to measure Earth's radius?

everyday science MCQ #1667

  1. Question 1

    Q1. Who was the first to measure Earth's radius?

    • A) Galileo
    • B) Copernicus
    • C) Ptolemy
    • D) Eratosthenes

    Answer: Eratosthenes

    Explanation: Eratosthenes (276–194 BC) calculated Earth's circumference by comparing the angles of shadows cast at Alexandria and Syene at noon on the summer solstice, then derived the radius.