Ch 2 - L4 Measuring devices

A galvanometer scale is divided such that every division indicates 2 μA.If the pointer of the galvanometer deflects to half the scale when a current of 40 μA passes through the galvanometer coil, calculate the whole number of divisions of the galvanometer.

• 10 divisions

• 80 divisions

• 20 divisions

• 40 divisions

A galvanometer of resistance 240 Ω allows only 4% of the main current after connecting a shunt resistance. What is the value of shunt resistance?

• 10 Ω

• 20 Ω

• 8 Ω

• 5 Ω

A galvanometer having a resistance of 8 ohms is shunted by a resistance 2 ohms. If the total current is 1 A, the part of it passing through the galvanometer will be :

• 0.25A

• 0.2A

• 0.8A

• 0.5A

A galvanometer of coil's resistance R so the shunt resistor decreases its sensitvity to quarter is .........

• R

• 0.5R

• 0.33R

• 0.25R

The shunt resistor changing a galvanometer to a more accurate device is

• 0.1 ohm

• 0.01 ohm

• 0.001 ohm

• 1 ohm

• 6‎ ‎000 Ω

• 15‎ ‎000 Ω

• 12‎ ‎000 Ω

• 9‎ ‎000 Ω

A voltmeter that has a resistance 𝑅 can measure potential difference up to 𝑉.If we added a multiplier resistance of value 2𝑅 in series to it, what would the maximum potential difference it can measure be?

• 
  2𝑉

• 𝑉

• 3𝑉

• 𝑉/3

A galvanometer of resistance 0.5 Ω that gives full-scale deflection when a current of 3 mA passes through it is converted to a voltmeter by connecting it in series with a multiplier resistance of 2‎ ‎999.5 Ω.What is the maximum potential difference this voltmeter is capable of measuring?

• 15 V

• 8.997 V

• 9 V

• 1.5 V

A galvanometer is connected in series to a variable multiplier resistor to construct a voltmeter. The graph below represents the relation between the maximum potential difference the voltmeter can measure and the value of the multiplier resistor. Then, the value of the resistance of the galvanometer equals......

• 2‎ ‎000 Ω

• 4‎ ‎000 Ω

• 6‎ ‎000 Ω

• 8‎ ‎000 Ω

A galvanometer with a resistance of 60 Ω that can measure currents up to 3 mA is connected to a 20 Ω resistor in parallel to form a device. If that device is connected in series with a 4‎ ‎985 Ω multiplier resistor to form a voltmeter, then the maximum potential difference this voltmeter is capable of measuring is.........

• 15 V

• 0.053 V

• 0.045 V

• 15.195 V