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The maximum current in a galvanometer ca...

The maximum current in a galvanometer can be 10 mA. Its resistance is `10 Omega`. To convert it into an ammeter of 1 A, what resistance should be connected in parallel with galvanometer (in `10^(-1)Omega)`?

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To solve the problem of converting a galvanometer into an ammeter, we need to determine the resistance that should be connected in parallel with the galvanometer. Here’s a step-by-step solution: ### Step 1: Understand the Given Values - Maximum current in the galvanometer, \( I_g = 10 \, \text{mA} = 10 \times 10^{-3} \, \text{A} \) - Resistance of the galvanometer, \( R_g = 10 \, \Omega \) - Desired maximum current for the ammeter, \( I = 1 \, \text{A} \) ### Step 2: Use the Formula for Shunt Resistance When a galvanometer is converted into an ammeter, a shunt resistance \( S \) is connected in parallel. The relationship between the currents is given by: \[ I = I_g + I_s \] where \( I_s \) is the current through the shunt. The potential difference across both the galvanometer and the shunt is the same: \[ I_g R_g = I_s S \] ### Step 3: Express \( I_s \) in Terms of \( I \) and \( I_g \) From the first equation, we can express \( I_s \): \[ I_s = I - I_g \] ### Step 4: Substitute \( I_s \) into the Voltage Equation Substituting \( I_s \) into the voltage equation gives: \[ I_g R_g = (I - I_g) S \] ### Step 5: Rearrange to Solve for \( S \) Rearranging the equation to solve for \( S \): \[ S = \frac{I_g R_g}{I - I_g} \] ### Step 6: Substitute the Known Values Now, substitute \( I_g = 10 \times 10^{-3} \, \text{A} \), \( R_g = 10 \, \Omega \), and \( I = 1 \, \text{A} \): \[ S = \frac{(10 \times 10^{-3}) \times 10}{1 - (10 \times 10^{-3})} \] ### Step 7: Calculate the Values Calculating the numerator: \[ (10 \times 10^{-3}) \times 10 = 0.1 \] Calculating the denominator: \[ 1 - 10 \times 10^{-3} = 1 - 0.01 = 0.99 \] Thus, \[ S = \frac{0.1}{0.99} \approx 0.10101 \, \Omega \] ### Step 8: Convert to the Required Format Since the problem asks for the answer in \( 10^{-1} \, \Omega \): \[ S \approx 0.10101 \, \Omega \approx 10^{0} \, \Omega \text{ (approximately)} \] Thus, we can express it as: \[ S \approx 1.01 \times 10^{-1} \, \Omega \] ### Final Answer To convert the galvanometer into an ammeter of 1 A, the resistance that should be connected in parallel with the galvanometer is approximately: \[ S \approx 10^{-1} \, \Omega \]

To solve the problem of converting a galvanometer into an ammeter, we need to determine the resistance that should be connected in parallel with the galvanometer. Here’s a step-by-step solution: ### Step 1: Understand the Given Values - Maximum current in the galvanometer, \( I_g = 10 \, \text{mA} = 10 \times 10^{-3} \, \text{A} \) - Resistance of the galvanometer, \( R_g = 10 \, \Omega \) - Desired maximum current for the ammeter, \( I = 1 \, \text{A} \) ### Step 2: Use the Formula for Shunt Resistance ...
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