Here is the highly detailed, arcane, complex, technical form of Ohm's Law that is needed in order to answer this question ===> V = I · R .
Voltage = (current) x (resistance)
Voltage = (2 Ampere) x (8 Ω)
Voltage = 16 volts
Using ohms law
[tex]\boxed{\sf \dfrac{V}{I}=R}[/tex]
[tex]\\ \sf\longmapsto V=IR[/tex]
[tex]\\ \sf\longmapsto V=8(2)[/tex]
[tex]\\ \sf\longmapsto V=16V[/tex]