Home
Class 12
PHYSICS
When a voltage measuring device is conne...

When a voltage measuring device is connected to a.c. mains the meter shows the steady input voltage of `220 V`. This means

A

input voltage cannot be AC voltage, but a DC voltage

B

maximum input voltage is 220 V

C

the meter reads not v but `ltv^(2)gt` and is calibrated to read `sqrt(ltv^(2)gt)`

D

the pointer of the meter is stuck by some mechanical defect.

Text Solution

Verified by Experts

The correct Answer is:
C
The voltmeter connected to AC mains reads mean value `v^(2)` and is calibrated in such a way that it gives value of `v^(2)` which is multiplied by from factor to given rms value.
Promotional Banner

Similar Questions

Explore conceptually related problems

The peak voltage in a 220 V AC source is

The peak voltage in a 220 V AC source is

What is the peak value of the voltage of a 220V ac line?

(a) Draw graphs showing the variations of inductive reactnace and capacitive reactance with frequency of the applied ac source . (b) Draw the phasor diagram for a series RC circuit connected to an ac source. (c ) An alternating voltage of 220 V is applied across a device X , a current of 0.25 A flows , which lag behind the applied voltage in phase by (pi)/(2) radian . If the same voltage is applied across another device Y , the same current flows but now it is in phase with the applied voltage . (i) Name the devices X and Y. (ii) Calculate the current flowing in the circuit when the same voltage is applied across the series combination of X and Y.

When an alternating voltage of 220 V is applied across a device P , a current of 0.25 A flows through the circuit and it leads the applied voltage by a angle pi/2 radian. When the same voltage source is connected across another device Q , the same current is observed in the circuit but in phase with the applied voltage. What is the current when the same source is connected across a series combination of P and Q ?

When an alternating voltage of 220 V is applied across a device P , a current of 0.25 A flows through the circuit and it leads the applied voltage by a angle pi/2 radian. When the same voltage source is connected across another device Q , the same current is observed in the circuit but in phase with the applied voltage. What is the current when the same source is connected across a series combination of P and Q ?

In a voltage regulating of zener diode, the graph of output voltage v_(o) versus input voltage v_(1) is

An electric bulb rated '220 V, 60 W' glows when connected with 220 V mains. Another identical bulb is connected in series with the first one and the system is connected across the 220 V mains. Draw a diagram to show the arrangement and find : (a) the rate of consumption of energy in each bulb, and (ii) total power consumed.

An electric heater rated 220 V and 550 V is connected to AC mains. The current drawn by it is

When a battery connected across a resistor of 16 Omega , the voltage across the resistor is 12 V. When the same battery is connected across a resistor of 10 Omega , voltage across it is 11 V. The internal resistance of the battery (in ohm) is