Помогите пожалуйста 4. Complete these sentences using while. Follow the model.

Model: The ammeter is used to measure the value of current....

The ammeter is used to measure the value of current while the ohmmeter is used to measure the value of resistance.

1. The ohmmeter is used to measure the value of resistance...........

2. The ammeter is connected in series...

3. When the ammeter is used to measure the value of current the circuit should be opened



5. Pair work. Put these questions to your groupmate. Let him/her answer
them.

1.What is the ammeter used for?

2. What is the voltmeter used for?

3. What is the ohmmeter used for?

4. What terminals does a meter have?

5. Should the measured circuit be opened when the voltmeter is used?

6. Should the measured circuit be opened when the ammeter is used?

7. In what way should the voltmeter be connected to the circuit?

8. In what way should the ammeter be connected to the circuit?

9. What is the difference between a voltmeter and an ammeter?

10. What common meters are used to measure the values in a circuit?



6. Solve the following problems:

1. Suppose the ammeter scale reads 1.9 amp, the voltmeter scale reads 2.4 V; how much is the value of resistance in the measured circuit?

2. Suppose the ohmmeter scale reads 75 ohms, the voltmeter scale reads 220 V; how much is the value of current in the measured circuit?

3. Suppose that you have a series circuit consisting of three resistors and a voltage source. R1 = 0.18 ohm, R2= 1.15 ohms, R3 = 2 ohms, I=10 amp. Find the voltage drop across each resistor; find the value of voltage in the circuit. Suppose R1 gets open. What does it result in?

4. Two resistors are connected in series. Ri = 7,000, R2= 2,200, I = 110 amp. Find the voltage drop across each resistor. Suppose no current passes through the circuit, what does it result from?

1. Complete these sentences using "while"

1. The ohmmeter is used to measure the value of resistance while the ammeter is used to measure the value of current.

2. The ammeter is connected in series while the voltmeter is connected in parallel to the component whose voltage is being measured.

3. When the ammeter is used to measure the value of current, the circuit should be opened while ensuring that the current only flows through the ammeter to avoid incorrect measurements.

5. Pair work. Put these questions to your groupmate. Let him/her answer them.

1. What is the ammeter used for?

   • The ammeter is used to measure the electric current flowing through a circuit.

2. What is the voltmeter used for?

   • The voltmeter is used to measure the electrical potential difference (voltage) between two points in a circuit.

3. What is the ohmmeter used for?

   • The ohmmeter is used to measure the resistance in a circuit or a component.

4. What terminals does a meter have?

   • A typical meter (such as ammeter, voltmeter, or ohmmeter) has two terminals: one positive (+) and one negative (−).

5. Should the measured circuit be opened when the voltmeter is used?

   • No, the measured circuit does not need to be opened when using a voltmeter, as it is connected in parallel across the component to measure the voltage.

6. Should the measured circuit be opened when the ammeter is used?

   • Yes, the circuit should be opened when using an ammeter, as it must be connected in series with the circuit to measure the current.

7. In what way should the voltmeter be connected to the circuit?

   • The voltmeter should be connected in parallel across the component or part of the circuit where the voltage is to be measured.

8. In what way should the ammeter be connected to the circuit?

   • The ammeter should be connected in series with the circuit to measure the current flowing through it.

9. What is the difference between a voltmeter and an ammeter?

   • The voltmeter measures the voltage (potential difference) across a component and is connected in parallel, while the ammeter measures the current flowing through the circuit and is connected in series.

10. What common meters are used to measure the values in a circuit?

• Common meters used in electrical circuits include the ammeter (for measuring current), voltmeter (for measuring voltage), and ohmmeter (for measuring resistance).

6. Solve the following problems:

1. Suppose the ammeter scale reads 1.9 A, the voltmeter scale reads 2.4 V; how much is the value of resistance in the measured circuit?

   To find the resistance, we can use Ohm’s Law:

   $$R = \frac{V}{I}$$

   Where:

   • $V = 2.4 \, \text{V}$
   • $I = 1.9 \, \text{A}$

   Substituting the values:

   $$R = \frac{2.4}{1.9} = 1.26 \, \Omega$$

   So, the resistance in the circuit is 1.26 ohms.

2. Suppose the ohmmeter scale reads 75 ohms, the voltmeter scale reads 220 V; how much is the value of current in the measured circuit?

   Again, we use Ohm’s Law to find the current:

   $$I = \frac{V}{R}$$

   Where:

   • $V = 220 \, \text{V}$
   • $R = 75 \, \Omega$

   Substituting the values:

   $$I = \frac{220}{75} \approx 2.93 \, \text{A}$$

   So, the current in the circuit is approximately 2.93 amperes.

3. Suppose that you have a series circuit consisting of three resistors and a voltage source. $R_1 = 0.18 \, \Omega$, $R_2 = 1.15 \, \Omega$, $R_3 = 2 \, \Omega$, $I = 10 \, \text{A}$. Find the voltage drop across each resistor; find the value of voltage in the circuit. Suppose $R_1$ gets open. What does it result in?

   First, calculate the total resistance in the circuit:

   $$R_{total} = R_1 + R_2 + R_3 = 0.18 + 1.15 + 2 = 3.33 \, \Omega$$

   The total voltage can be found using Ohm’s Law:

   $$V = I \times R_{total} = 10 \times 3.33 = 33.3 \, \text{V}$$

   Now, calculate the voltage drop across each resistor using Ohm’s Law for each one:

   • Voltage drop across $R_1$: $$V_1 = I \times R_1 = 10 \times 0.18 = 1.8 \, \text{V}$$
   • Voltage drop across $R_2$: $$V_2 = I \times R_2 = 10 \times 1.15 = 11.5 \, \text{V}$$
   • Voltage drop across $R_3$: $$V_3 = I \times R_3 = 10 \times 2 = 20 \, \text{V}$$

   If $R_1$ gets open, the circuit will be broken, and no current will flow through the circuit, meaning the total current will be zero.

4. Two resistors are connected in series. $R_1 = 7,000 \, \Omega$, $R_2 = 2,200 \, \Omega$, $I = 110 \, \text{A}$. Find the voltage drop across each resistor. Suppose no current passes through the circuit, what does it result from?

   First, calculate the total resistance in the series circuit:

   $$R_{total} = R_1 + R_2 = 7000 + 2200 = 9200 \, \Omega$$

   Now, calculate the total voltage using Ohm’s Law:

   $$V = I \times R_{total} = 110 \times 9200 = 1,012,000 \, \text{V}$$

   The voltage drop across each resistor:

   • Voltage drop across $R_1$: $$V_1 = I \times R_1 = 110 \times 7000 = 770,000 \, \text{V}$$
   • Voltage drop across $R_2$: $$V_2 = I \times R_2 = 110 \times 2200 = 242,000 \, \text{V}$$

   If no current passes through the circuit, this means the circuit is open, possibly due to a break in the wiring or a faulty component, which prevents the flow of current.