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प्रश्न
State Newton’s first law of motion. Give two examples to illustrate Newton’s first law of motion.
उत्तर
According to Newton’s first law of motion:
A body at rest will remain at rest and a body in motion will continue in motion in a straight line with a constant velocity, unless it is compelled by an external force to change its state of rest or of uniform motion.
Examples:
(a) A book lying on a table cannot change its state of rest unless an external force is applied on the book.
(b) A car set free on a sloppy road will continue to be in motion unless an external force applied by hands or brakes to bring the car to rest.
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