Question

R1=R2=R3=10 Ω 

Tính R?

Answer 1

MCD:R1//R2//R3

R=\(\dfrac{R_1R_2R_3}{R_2R_3+R_2R_1+R_1R_3}=\dfrac{10\cdot10\cdot10}{10\cdot10+10\cdot10+10\cdot10}=\dfrac{10}{3}\)(ôm)

Answer 2

ta có mạch điện tương đương

\(\dfrac{1}{R}\)=\(\dfrac{1}{R1}\)+\(\dfrac{1}{R2}\)+\(\dfrac{1}{R3}\)

⇒\(\dfrac{1}{R}\)=\(\dfrac{1}{10}\)+\(\dfrac{1}{10}\)+\(\dfrac{1}{10}\)

⇒\(\dfrac{1}{R}\)=\(\dfrac{3}{10}\)⇒R=\(\dfrac{10}{3}\)