Video narration
Jolte thaka mombatite momta ki sotyi dhongsho hoye jay? Na, shudhu chokher samne theke odrissho hoy. Mom gole, bashpe porinoto hoy, tarpor batasher oxygen er songe jole. Toiri hoy carbon dioxide, joliyobashpo, ar aro kichu podartho, jegulo beshirbhagoi odrissho gas hoye charpasher batase choriye jay. Tai momer bhor harayni; mom ar oxygen miliye notun podartho hoyeche. Bondho systeme etii conservation of mass, bhor songrokkhito thake. Ebar aguner ushnota ar alo dekhun. Momer bhetore joma rashayonik shokti beriye eshe tap, alo, ebong ashpash e choriye pora shoktite bodle jay. Etai conservation of energy, shokti haray na, rup bodlay. Tobe boro chobite, parmanobik prokriyaye bhor o shokti eke onnye bodlate pare, ei shomporkotii E = mc2. Tai sekhane hisaber asal poriman mass-energy, mot bhor-shokti. Tahole mombatir mom kothay gelo? Gase bodle batase gelo, ar tar rashayonik shokti holo tap o alo. Kichui udhao hoyni; puro systemer mot mass-energy oporibortito ache.