Question

How was Aristarchus's explanation of the movement of objects in the sky different from other scientists' earlier explanations? Check all that apply.

He discovered Venus’s phases.

He argued that Earth rotates on its axis.

He explained the concept of retrograde motion.

He described the epicycles of the planets in the sky.

He stated that the Sun is the center of the solar system.

Answer 1

Newton's laws of motion are three physical laws that, together, laid the foundation for classical mechanics. They describe the relationship between a body and the forcesacting upon it, and its motion in response to those forces. More precisely, the first law defines the force qualitatively, the second law offers a quantitative measure of the force, and the third asserts that a single isolated force doesn't exist. These three laws have been expressed in several ways, over nearly three centuries,[1] and can be summarised as follows:

First law:In an inertial frame of reference, an object either remains at rest or continues to move at a constant velocity, unless acted upon by a force.[2][3]Second law:In an inertial frame of reference, the vector sum of the forces F on an object is equal to the mass mof that object multiplied by the acceleration a of the object: F = ma. (It is assumed here that the mass m is constant – see below.)Third law:When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.

Answer 2

"Aristarchus" was the first who 'stated' that the 'Sun' is the 'centre' of the 'solar system'.

EXPLANATION:

This theory was in opposition to the theory proposed that the 'earth' was at the 'centre' of the heavenly bodies and that all other objects rotated around it. Aristarchus proposed that the sun was at the 'centre' and the earth moved around it. This was the heliocentric approach to movement of 'objects' in the sky.