Question

Study the following circuit and answer the questions that follow :
(a) State the type of combination of the two resistors in the circuit.
(b) How much current is flowing through :
(i) 10 ohm resistor (ii) 15 ohm resistor.
(c) What is the ammeter reading ?
(d) Define SI unit of the current




CBSE Class X Science LA (5 Marks)

Answer 1

(a) Type of combination:

The image given in the question is attached below.

The resistors given in the circuit is parallel combination. So, this is a parallel resistor.

When the resistors are connected in parallel combination, then the reciprocal of equivalent resistor is equal to sum of reciprocal of individual resistors.

(b) Current flowing through the circuit:

(i) 10 ohm resistor:

$\bold{I_{1}=\frac{V}{R_{1}}}$

On substituting the values, we get,

$\bold{I_1=\frac{3 \ V}{10 \ \Omega}}$

$\bold{\therefore I_1 = 0.3 \ A}$

(ii) 15 ohm resistor:

$\bold{I_{2}=\frac{V}{R_{2}}}$

On substituting the values, we get,

$\bold{I_2=\frac{3 \ V}{15 \ \Omega}}$

$\bold{\therefore I_2 = 0.2 \ A}$

(c) Reading in ammeter:

The resistors are in parallel, so, the current flowing through the resistors are different. So, we need to find the sum of current flowing through the individual resistors.

$\bold{I=I_{1}+I_{2}}$

On substituting the values, we get,

$\bold{I=0.3+0.2}$

$\bold{\therefore I = 0.5 \ A}$

(d) SI unit of current:

Current is measured with the unit Ampere.

Answer 2

Answer:

Explanation:

Voltage V = 3 volts

Resistance R1 = 10 Ohms and R2 = 15 Ohms

(a) In the circuit, the two resistors are connected in parallel. Please refer the attached picture for the circuit diagram.

(b) Current through first resistor = I1 = v/R1 = 3 / 10 = 0.3 Amperes.

Current through the second resistor = I2 = v/R2 = 3 / 15 = 0.2 Amperes.

(c) Ammeter reading will be I = I1 + I2 (parallel connection) = 0.3 + 0.2 = 0.5 Amperes.