Question

Find the resistance (in ohms) that must be placed in series with a 25.0-Ω galvanometer (50.0-μA sensitivity) to allow it to be used as a voltmeter with a 3000-V full-scale reading.

(a) 5.99 × 10^5 Ω
(b) 6.25 × 10^5 Ω
(c) 6.75 × 10^5 Ω
(d) 7.21 × 10^5 Ω

Answer 1

The resistance that must be placed in series with the galvanometer to allow it to be used as a voltmeter with a 3000-V full-scale reading is 6.25 × 10^5 Ω.

Step-by-step explanation:

To calculate the resistance that must be placed in series with the galvanometer, we can use the formula:

R = (V / G) - G

Where R is the resistance we need to find, V is the full-scale reading (3000 V in this case), and G is the galvanometer sensitivity (50.0 μA in this case).

Plugging in the values, we get:

R = (3000 V / 50.0 μA) - 50.0 μA = 6.25 × 10^5 Ω

Therefore, the resistance that must be placed in series with the galvanometer is 6.25 × 10^5 Ω.