_____ is the external agency applied on a body to change its state of rest or uniform motion.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. Force
Force is the external agency applied to a body to change its state of rest or uniform motion.
- According to Newton's first law, if a body is at rest or moving in a straight line at a constant speed, it will continue to move at that speed or remain at rest until acted with by a force.
- The law of inertia is the name given to this postulate.
- Galileo Galilei first proposed the law of inertia for Earth's horizontal motion, and René Descartes later generalized it.