English to Indonesian
| efficiency of a luminous source | randemen cahaya lampu |
| efficiency | kedayagunaan, efisiensi, kecakapan, ketangkasan |
| of | kd. 1 a glass of milk segelas susu. 2 dari. 3 kurang. 4 akan. 5 untuk. 6 karena. 7 diantara. |
| luminous | berkilauan, bercahaya, bersinar |
| source | sumber, asal |