How will the reading in the ammeter `A` of Fig. 6.39 be affected if another identical bulb `Q` is connected in parallel to `P` as shows. The voltage in the mains is maintained at a constant value.

The ammeter shows in Fig. 6.73. Consists of 480 Omega coil connected in parallel to 20 Omega shunt. The reading of the ammeter comes out to be 1//'**'A . What 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.

Read the following text and answer the following questions on the basis of the same: Shunt resistance: The ammeter shunt is the device which provides the low resistance path to the flow of current. It is connected in parallel with the ammeter. In some ammeter the shunt is in-built inside the instrument while in others it is externally connected to the circuit. Manganin and Constantan are used for making the shunt of DC and AC ammeter respectively. Ammeters are designed for measurement of low current. For measuring high current, the shunt is connected in parallel to the ammeter. The significant portion of the current passes to the shunt because of the low resistance path and little amount of current passes through the ammeter. The shunt is connected in parallel to the ammeter because of which the voltage drops across the meter and shunt remain the same. Thus, the movement of the pointer is not affected by the shunt. Let us consider that the current to be measured is I. The circuit has ammeter and shunt connected parallel to each other. The ammeter is designed for measurement of small current say, I_(m) . The magnitude of the current I passes through the meter is very high, and it will burn the meter. So, for measuring the current I the shunt is required in the circuit. As the shunt connects in parallel with the ammeter, thus the same voltage drops occur between them: I_(Sh)R_(SH)=I_(m)R_(m) :.R_(SH)=I_(m)R_(m)//I_(SH) Shunt current I_(SH)=I-I_(m) So, R_(SH)=I_(m)R_(m)//(I-I_(m)) :.I//I_(m)=1+(R_(m)//R_(SH)) The ratio of the total current to the current required for the movement of the ammeter coil is called the multiplying power of the shunt. :. The multiplying power =m=I//L_(m) R_(SH)=R_(m)//(m-1) The following are the requirements of the shunt. • The resistance of the shunt should remain constant with time. • The temperature of the material-should remain same even though substantial current flows through the circuit. Materials used for making shunt of DC and AC ammeter are respectively

Read the following text and answer the following questions on the basis of the same: Shunt resistance: The ammeter shunt is the device which provides the low resistance path to the flow of current. It is connected in parallel with the ammeter. In some ammeter the shunt is in-built inside the instrument while in others it is externally connected to the circuit. Ammeters are designed for measurement of low current. For measuring high current, the shunt is connected in parallel to the ammeter. The significant portion of the current passes to the shunt because of the low resistance path and little amount of current passes through the ammeter. The shunt is connected in parallel to the ammeter because of which the voltage drops across the meter and shunt remain the same. Thus, the movement of the pointer is not affected by the shunt. Let us consider that the current to be measured is I. The circuit has ammeter and shunt connected parallel to each other. The ammeter is designed for measurement of small current say, I_(m) . The magnitude of the current I passes through the meter is very high, and it will burn the meter. So, for measuring the current I the shunt is required in the circuit. As the shunt connects in parallel with the ammeter, thus the same voltage drops occur between them: I_(Sh)R_(SH)=I_(m)R_(m) :.R_(SH)=I_(m)R_(m)//I_(SH) Shunt current I_(SH)=I-I_(m) So, R_(SH)=I_(m)R_(m)//(I-I_(m)) :.I//I_(m)=1+(R_(m)//R_(SH)) The ratio of the total current to the current required for the movement of the ammeter coil is called the multiplying power of the shunt. :. The multiplying power =m=I//L_(m) R_(SH)=R_(m)//(m-1) The following are the requirements of the shunt. • The resistance of the shunt should remain constant with time. • The temperature of the material-should remain same even though substantial current flows through the circuit. Manganin and Constantan are used for inaking the shunt of DC and AC ammeter respectively. What is multiplying power of the shunt?

A parallel plate air-filled capacitor is charged by connecting it across a voltage source for a long time. It is then disconnected from the source and connected across a voltmeter. How the voltage reading in the voltmeter will be affected if a dielectric is inserted between the plates of the capacitor? State your assumptions if any in the explanation.

An ideal ammeter (zero resistance) and an ideal voltmeter (infinite resistance) are connect as shows in Fig. 6.47 . The ammeter and the voltmeter readings are