Question

A circuit consists of a resistor, a battery and an ammeter. The ammeter shows a current of 0.2A when the resistor is 120. If you want to get a current of 0.15A, what resistor should be used to replace the current resistor?

Answer 1

A resistor of 160 ohms should be used to replace the current resistor

Step-by-step explanation:

Applying,

Ohm's Law

V = IR................... Equation 1

Where V = Voltage of the battery, I = current, R = Resistance

From the question,

Given: I = 0.2 A, R = 120 ohms.

Substitute these values into equation 1

V = 0.2×120

V = 24 V

IF a current of 0.15 A is required,

make R the subject of equation 1

R = V/I............... Equation 2

Given: V = 24 V, I = 0.15 A

Substitute these values into equation 2

R = 24/0.15

R = 160 ohms.

Hence a resistor of 160 ohms should be used to replace the current resistor