Question

give two examples of periodic motion with explanation

Answer 1

Motion of piston of an engine
Motion of a pendulum of a clock
Motion of see saw

Answer 2

"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.