Hi Lalit,
"Was submitted" is the past simple tense; "has been submitted" is the present perfect. The difference between them is a grammatical topic that usually needs a whole class to explain! :-)
Briefly, the past simple talks about something that happened in the past, in a time period that is finished and gone.
The present perfect talks about something that happened in the past, but has an effect in the present. Compare "I switched on the light" and "I have switched on the light". In the first example, the light may now be on or off - we don't know. The second example tells us that the light is now on! The event happened in the past, but the effect (the light is on) is in the present.
So, in your examples, "was submitted" tells us that something was submitted in the past; it tells us nothing about the present. "Has been submitted" tells us that something was submitted in the recent past, and its state (or status) is now "submitted" - in the present.