Firebase 10 random Fetch like RAND() in PHP

Please i am building an App that needs to fetch 10 objects randomly from my firebase Database

I am able to do this easily in PHP MYSQL using REST but i have tried it in firebase and no head way so i need help.

i just want my $firebasArray to always hold 10 random object anytime a request is made and i have about 500 objects in the database. But i just want to randomly get 10 each time i fetch data from the firebase database.

Please any simple code will be appreciated thanks