Calculate the electric current in the circuit shown below.

Explanation

Any current that passes through the `10Omega` resistor also passes through the `5Omega` resistor, i.e. `10Omega` and `5Omega` resostor are connected in series. Their equivalent resistance is `R_("eq")=10Omega+5Omega=15Omega`.
The equivalent circuit is shown in the above figure
The current is
`i=(V)/(R_("eq"))=(7.5V)/(15Omega)=0.5A`