820. ভূমিকম্পে সৃষ্ঠ তরঙ্গ কি ধরণের-
ব্যাখ্যা: When seismic waves are first created, they travel outwards in all direction from their source. Body waves travel through the interior of the earth, and have two main types:
P- Waves (Primary waves)
are Longitudinal Waves. (লাম্বিক তরঙ্গ)
S-Waves (Secondary waves)
are Transverse Waves. (আড় তরঙ্গ)