first harmonic, second harmonic third harmonic; first harmonic is it is called fundamental for that n equal to 1 for n equal to 1 then that string you will see in this form ok, the string you will see in this form. this is called anti node and this wave y equal to 0 this is called node ok.
पहिल्या हर्मोनीक ला मूलभूत मोड म्हणतात.