4) You have a 10 ohm resistor connected in series with an ammeter. The voltage applied to the whole circuit is 1.2 volts. At the same time you have a voltmeter connected across the 10 ohm resistor and voltmeter reads 0.9 volts. The circuit draws a total of 0.5 amps. Can you determine resistance of the ammeter

Explanation:

Given that,

Resistor R = 10 ohms

The resistor is connected in series with an ammeter to calculator the current that flows in the circuit.

Voltage applied V = 1.2 V

There is also a voltmeter across the 10 ohms resistor to know the potential difference across the resistor.

If the voltmeter reads 0.9V.

This shows that the voltage across the resistor is 0.9V

Vr = 0.9V, which is the terminal voltage

The ammeter reads a current of 0.5amps

This show that, the current that flow in the circuit is 0.5A

Ir = 0.5A

Internal resistance r of the ammeter?

Using KVL

V = I(r+R)

V = Ir + IR

Where IR is the terminal voltage Vr

V = Ir + Vr

Ir = V—Vr

Ir = 1.2—0.9

0.5r = 0.3

r = 0.3/0.5

r = 0.6 ohms