Question

V(open circuit)=? Rth=? (R=50,P=?) (R=12.5,P=?)

Answer 1

75 V

Explanation:

In the closed circuit you have a `Delta V` of (100-50)= 50V and a total resistence of `50 Omega` because the three resistences are in series. So the electtric current is of
`I= V/R= (50V)/(50 Omega)= 1 A`
So in the resistor of `25 Omega`you have a
`Delta V = RI = 25 Omega xx 1 A =25 V` and
`V_(a-b)` in the open circuit will be
`V=100V-25V = 75 V`