What do you mean by electromagnet induction?under what condition is this phenomenon possible?

Electromagnetic induction is a phenomenon in which a changing magnetic field across a loop of wire results in the generation of an induced emf. When there is relative motion between a magnet and the coil, magnetic flux changes and hence an electromotive force is generated in the coil.

the word that best describes martin luther king jr.'s tone in the video is dignified

martin luther king, jr. was a social activist and baptist minister who played a key role in the american civil rights movement from the mid-1950s until his assassination in 1968. the video shows his manner and attitude having or showing a composed or serious manner that is worthy of respect so dignified is the correct answer