To address the questions in your circuit diagram, let's first clearly outline Ohm’s Law and the calculations related to the resistors and current in the circuit.
Question 4.1 [2 marks]
Define the term OHM’s LAW in words.
Ohm’s Law states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) of the conductor. This can be expressed mathematically as \( V = I \times R \).
Question 4.2 [4 marks]
Calculate the effective resistance of the circuit.
Assuming the resistors are connected in parallel, we use the formula for total resistance \( R_{total} \) in parallel connections:
\[ \frac{1}{R_{total}} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} \]
Where \( R_1 = 6 , \Omega \), \( R_2 = 5 , \Omega \), and \( R_3 = 4 , \Omega \).
\[ \frac{1}{R_{total}} = \frac{1}{6} + \frac{1}{5} + \frac{1}{4} \] Calculating each term:
\[ \frac{1}{R_{total}} = \frac{10}{60} + \frac{12}{60} + \frac{15}{60} = \frac{37}{60} \]
Therefore,
\[ R_{total} = \frac{60}{37} \approx 1.62 , \Omega \]
Question 4.3 [2 marks]
Calculate the current reading on the ammeter.
Using Ohm's Law \( V = I \times R \), we can rearrange to find current \( I \):
\[ I = \frac{V}{R_{total}} = \frac{18 , V}{R_{total}} \approx \frac{18}{1.62} \approx 11.11 , A \]
Question 4.4 [2 marks]
Calculate the Voltmeter reading across the parallel connection.
In a parallel circuit, the voltage across each branch is the same. Since the entire circuit is powered by an 18V battery, the Voltmeter reading across the parallel connection will also be:
\[ V = 18 , V \]
Question 4.5 [2 marks]
Calculate the Voltmeter reading across the 6-ohm resistor.
As established in the previous answer, in parallel circuits, the voltage across each resistor is the same as the total voltage supplied by the battery. Therefore, the Voltmeter reading across the 6-ohm resistor is also:
\[ V = 18 , V \]
These calculations assume that the three resistors are indeed in parallel. If the configuration of the circuit were to differ (e.g., series or a combination), the approach to calculate the effective resistance and subsequent values would need to be adjusted accordingly.
3 answers