Home
Class 12
PHYSICS
In balanced meter bridge, the resistance...

In balanced meter bridge, the resistance of bridge wire is `0.1Omega cm` . Unknown resistance X is connected in left gap and `6Omega` in right gap, null point divides the wire in the ratio 2:3 . Find the current drawn the battery of 5V having negligible resistance

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we will follow these steps: ### Step 1: Calculate the total resistance of the bridge wire The resistance of the bridge wire is given as \(0.1 \, \Omega/\text{cm}\) and the length of the wire is \(100 \, \text{cm}\). \[ \text{Total resistance of the wire} = \text{Resistance per cm} \times \text{Length} = 0.1 \, \Omega/\text{cm} \times 100 \, \text{cm} = 10 \, \Omega \] ### Step 2: Understand the ratio in which the wire is divided The null point divides the wire in the ratio \(2:3\). This means that the left segment of the wire (where the unknown resistance \(X\) is connected) is \(2\) parts, and the right segment (where \(6 \, \Omega\) is connected) is \(3\) parts. Let the total length of the wire be \(L = 100 \, \text{cm}\). - Length of left segment = \( \frac{2}{2+3} \times 100 \, \text{cm} = \frac{2}{5} \times 100 \, \text{cm} = 40 \, \text{cm} \) - Length of right segment = \( \frac{3}{2+3} \times 100 \, \text{cm} = \frac{3}{5} \times 100 \, \text{cm} = 60 \, \text{cm} \) ### Step 3: Calculate the resistance of each segment of the wire Using the resistance per cm, we can calculate the resistance of each segment: - Resistance of left segment (40 cm): \[ R_1 = 0.1 \, \Omega/\text{cm} \times 40 \, \text{cm} = 4 \, \Omega \] - Resistance of right segment (60 cm): \[ R_2 = 0.1 \, \Omega/\text{cm} \times 60 \, \text{cm} = 6 \, \Omega \] ### Step 4: Apply the Wheatstone bridge condition In a balanced meter bridge, the ratio of the resistances is given by: \[ \frac{X}{6} = \frac{R_1}{R_2} = \frac{4}{6} \] From this, we can find the unknown resistance \(X\): \[ X = 6 \times \frac{4}{6} = 4 \, \Omega \] ### Step 5: Calculate the equivalent resistance of the circuit Now we have: - Resistance \(X = 4 \, \Omega\) - Resistance of the wire segments: \(R_1 = 4 \, \Omega\) and \(R_2 = 6 \, \Omega\) The total resistance in the circuit is the sum of the resistances in series: \[ R_{\text{total}} = R_1 + R_2 = 4 \, \Omega + 6 \, \Omega = 10 \, \Omega \] ### Step 6: Calculate the current drawn from the battery Using Ohm's law, the current \(I\) drawn from the battery can be calculated as: \[ I = \frac{V}{R_{\text{total}}} = \frac{5 \, \text{V}}{10 \, \Omega} = 0.5 \, \text{A} \] ### Final Answer: The current drawn from the battery is \(0.5 \, \text{A}\). ---
Promotional Banner

Similar Questions

Explore conceptually related problems

In above question if resistance of meter bridge wire is 1 Omega /cm then the value of current / is

In a meter bridge, null point is 20 cm , when the known resistance R is shunted by 10 Omega resistance, null point is found to be shifted by 10 cm. Find the unknown resistance X .

In a meter bridge, null point is 20 cm , when the known resistance R is shunted by 10 Omega resistance, null point is found to be shifted by 10 cm. Find the unknown resistance X .

In a meter bride, null point is 20 cm , when the known resistance R is shunted by 10 Omega resistance, null point is found to be shifted by 10 cm . Find the unknown resistance X .

A wire connected in the left gap of a meter bridge balance a 10Omega resistance in the right gap to a point, which divides the bridge wire in the ratio 3:2. If the length of the wire is 1m. The length of one ohm wire is

In a metre bridge when the resistance in the left gap is 2Omega and an unknown resistance in the right gap, the balance point is obtained at 40 cm from the zero end. On shunting the unknown resistance with 2Omega find the shift of the balance point on the bridge wire.

In a meter bridge experiment the ratio of left gap resistance to right gap resistance is 2:3 the balance point from is

In a meter bridge circuit, resistance, in the left hand gap is 2Omega and an unknown resistance X is in the right hand gap as shown in figure below. The null point is found to be 40 cm from the left end of the wire. What resistance should be connected to X so that the new null point is 50 cm from the left end of the wire ?

In a meter bridge, the null point is found at a distance of 40 cm from A. If now a resistance of 12 Omega is connected in parallel with S, the null point occurs at 60 cm from A. Determine the value of R.

In the gives circuit, a meter bridge is shows in a balanced state. The bridge wire has a resistance of 1 Omega cm^(-1) . Find the value of the unknown resistance X and the current draws from the battery of negligible internal resistance.