Aproton beam in an accelerator carries a current of 134 µa. if the beam is incident on a target, how many protons strike the target in a period of 16.0 s?

The intensity of current is defined as the quantity of charge Q that passes through a certain point in a time :


In our problem, the current is 
while the time interval is 16.0 s, so we can use the previous equation to find the total charge that strikes the target in this time:


We know that each proton carries a charge of , so we can find the number of protons that strike the target by dividing the total charge by the charge of a single proton: