A resistor of unknown resistance and a 15-? resistor are connected across a 20-V emf in such a way that a 2.0 A current is observed in the emf. What is the value of the unknown resistance?

a.
75 ?

b.
12 ?

c.
7.5 ?

d.
30 ?

e.
5.0 ?


d

Physics & Space Science

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Physics & Space Science