Three resistors of 2ohms ,4ohms and 5ohms are connected in parallel .determine the total resistance in the system?

To find the total resistance in a parallel circuit, you can use the formula:

1/RTotal = 1/R1 + 1/R2 + 1/R3 + ...

In this case, the resistors are 2 ohms, 4 ohms, and 5 ohms. Plugging in the values:

1/RTotal = 1/2 + 1/4 + 1/5

To add these fractions, you need to find a common denominator:

1/RTotal = 10/20 + 5/20 + 4/20

1/RTotal = 19/20

To isolate RTotal, take the reciprocal of both sides:

RTotal = 20/19

Therefore, the total resistance in the system is approximately 1.05 ohms.