QPage 48-49: Q1: HC Verma: Concepts of Physics - Volume 1 Chapter-3 Rest and Motion Kinematics Page 48-49: Q1 Solution: Galileo was punished by the Church for teaching that the sun is …
Students often incorrectly apply the principle of relativity to argue that the geocentric and heliocentric frames are equally valid, ignoring that the Earth undergoes centripetal acceleration. Unlike uniform linear motion, rotational and accelerated frames are absolute and detectable via inertial effects like the Coriolis force, making the heliocentric model physically distinct.
Galileo was punished by the Church for teaching that the sun is stationary and the earth moves around it. His opponents held the view ....
Multiple Choice Options
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Step-by-Step Verified Solution
To "solve" this question, we have to separate kinematics (describing motion), dynamics (explaining why things move), and history/theology.
The short, direct answer is: No, they are not equally correct. Here is why, broken down step-by-step:
1. Relativity applies to uniform motion, not acceleration (or rotation)
Einstein and Galileo both agreed that absolute uniform (straight-line, constant-speed) motion has no meaning. However, the Earth does not move in a straight line at constant speed—it orbits the Sun, meaning it is constantly accelerating (changing direction).
Acceleration and rotation are absolute—you can feel them or measure them without looking outside.
If you put a Foucault pendulum at the North Pole, it swings in a plane while the Earth rotates beneath it. This proves the Earth is rotating. If the Earth were truly stationary and the Sun rotated around it, you would not measure this specific physical effect. The heliocentric model correctly predicts real, measurable inertial forces (Coriolis effect, centrifugal bulging at the equator) that the geocentric model cannot naturally explain without inventing bizarre, unphysical rules.
2. The "Stationary" Sun is a misleading statement
Galileo argued the Sun is stationary—but in absolute terms, that is also wrong. Our Sun orbits the center of the Milky Way galaxy at about 220 km/s. So, if we take "absolute motion" to mean motion relative to the universe at large, both Galileo and the Church were wrong about the Sun being absolutely stationary.
However, in a practical physics sense, the Sun is stationary relative to the solar system's center of mass (the barycenter). The massive Sun sits at the gravitational anchor point, and the much lighter Earth moves around it.
3. The geocentric view requires fictional physics
To make the Earth-stationary model work, you have to add epicycles (circles upon circles) to explain why planets sometimes move backward (retrograde motion). In modern terms, an Earth-centered frame is a non-inertial reference frame. If you do physics in that frame, you have to invent massive fictitious forces (like a giant centrifugal force pushing everything outward) to make the math work.
In the Sun-centered (heliocentric) frame, the laws of physics—specifically Newton's law of gravitation and Kepler's laws—are elegant, simple, and universal. An apple falls on Earth for the exact same reason the Earth orbits the Sun. The Church's model had no such unified physical explanation; it was purely geometric.
4. Galileo's punishment was not just about science
Historically, Galileo wasn't punished purely for the science; he was punished for challenging the Church's theological authority and interpreting Scripture (which said the Sun "stood still" in Joshua) in a literal, non-scientific way. The Church’s view was tied to Aristotelian physics and biblical literalism, not just a harmless "alternative coordinate system."
Final Verdict:
- Are they equally correct? No. The heliocentric model accurately describes the gravitational dynamics, mass distribution, and observed forces of the solar system. The geocentric model is merely a mathematically cumbersome coordinate transformation, not a valid physical reality.
- Are they equally wrong? No. Galileo was correct about the Earth moving around the Sun. He was only wrong about the Sun being absolutely stationary in the universe. The Church was fundamentally wrong about the physical structure of the solar system.