Question

Answer the following :
a. Define the density of a substance.What is its S.I. unit?
b. What is periodic motion? Give an example.
c. How will you determine the volume of an irregular solid, such as a small pebble? d. State any three differences between mass and weight of a body.​

Answer 1

Answer:

periodic motion | Definition, Examples, & Facts | Britannica Periodic motion, in physics, motion repeated in equal intervals of time. Periodic motion is performed, for example, by a rocking chair, a bouncing ball, a vibrating tuning fork, a swing in motion, the Earth in its orbit around the Sun, and a water wave.

Explanation:

this is the answer of B

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