Question

Voltage needed to raise current to 3.75a using 20,20,200 resistor set

Answer 1

Answer: The voltage needed is 35.7 V

Explanation:

Assuming that the resistors are arranged in parallel combination.

For the resistors arranged in parallel combination:

$\frac{1}{R}=\frac{1}{R_1}+\frac{1}{R_2}+\frac{1}{R_3}$

We are given:

$R_1=20\Omega\\R_2=20\Omega\\R_3=200\Omega$

Using above equation, we get:

$\frac{1}{R}=\frac{1}{20}+\frac{1}{20}+\frac{1}{200}\\\\\frac{1}{R}=\frac{10+10+1}{200}\\\\R=\frac{200}{21}=9.52\Omega$

Calculating the voltage by using Ohm's law:

$V=IR$         .....(1)

where,

V = voltage applied

I = Current = 3.75 A

R = Resistance = $9.52\Omega$

Putting values in equation 1, we get:

$V=3.75\times 9.52\\\\V=35.7V$

Hence, the voltage needed is 35.7 V

Answer 2

There are six different ways to arrange those resistors.

Each way leads to a different answer.

You didn't tell us how you want them connected.

The attached drawing shows them all.