In a parallel circuit, the current stays the same if you add a branch with the same resistance. So since an electrical current is a flow of charges, where are the extra charge particles coming from? Is there a limit to the number of charges in a circuit? Thanks

the current will actually split

Explanation:

it's true that once u add a resistor of the same resistance that is already present, the OVERALL current by the circuit will stay the same but it'll branch off equally across the newly added, so if we assume the total current was initially 10Amps for a single 1ohm resistor, if u add another 1ohm resistor, 5Amps will be split for both resistors

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.