Physics M.C.Q (1 Marks)

In the adjoining circuit, the e.m.f. of the cell is 2 volt and the internal resistance is negligible. The resistance of the voltmeter is 80 ohm. The reading of the voltmeter will be

We have a galvanometer of resistance 25 Ω. It is shunted by a 2.5 Ω wire. The part of total current that flows through the galvanometer is given as

The resistance of 10 metre long potentiometer wire is 1ohm/meter. A cell of e.m.f. 2.2 volts and a high resistance box are connected in series to this wire. The value of resistance taken from resistance box for getting potential gradient of 2.2 millivolt/metre will be

A voltmeter of resistance 1000 Ω gives full scale deflection when a current of 100 mA flow through it. The shunt resistance required across it to enable it to be used as an ammeter reading 1 A at full scale deflection is

In a potentiometer experiment, the galvanometer shows no deflection when a cell is connected across 60 cm of the potentiometer wire. If the cell is shunted by a resistance of 6Ω, the balance is obtained across 50 cm of the wire. The internal resistance of the cell is

A galvanometer whose resistance is 120 Ω gives full scale deflection with a current of 0.05 A so that it can read a maximum current of 10 A. A shunt resistance is added in parallel with it. The resistance of the ammeter so formed is

An ammeter whose resistance is 180 Ω gives full scale deflection when current is 2 mA. The shunt required to convert it into an ammeter reading 20 mA (in ohms) is.

A potentiometer wire has length 10 m and resistance 20Ω. A 2.5 V battery of negligible internal resistance is connected across the wire with an 80 Ω series resistance. The potential gradient on the wire will be

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

In the following Wheatstone bridge P/Q = R/S. If key K is closed, then the galvanometer will show deflection

A moving coil galvanometer has a resistance of 50 Ω and gives full scale deflection for 10 mA. How could it be converted into an ammeter with a full scale deflection for 1A.

The net resistance of a voltmeter should be large to ensure that

Constantan wire is used in making standard resistances because its.

A 100 V voltmeter of internal resistance 20 kQ in series with a high resistance R is connected to a 110 V line. The voltmeter reads 5 V, the value of R is

The resistance of an ideal voltmeter is

If only 2% of the main current is to be passed through a galvanometer of resistance G, then the resistance of shunt will be

The resistance of a galvanometer is 50 ohms and the current required to give full scale deflection is 100μA. In order to convert it into an ammeter, reading upto 10A, it is necessary to put a resistance of

A potentiometer wire of length 1 m and resistance 10 W is connected in series with a cell of emf 2V with internal resistance 1 W and a resistance box including a resistance R. If potential difference between the ends of the wire is 1 mV, the value of R is

A potentiometer circuit shown in the figure is set up to measure e.m.f. of a cell E. As the point P moves from X to Y the galvanometer G shows deflection always in one direction, but the deflection decreases continuously until Y is reached. In order to obtain balance point between X and Y it is necessary to

In an experiment to measure the internal resistance of a cell by potentiometer, it is found that the balance point is at a length of 2m when the cell is shunted by a 5 Ω resistance; and is at a length of 3m when the cell is shunted by a 10 Ω resistance. The internal resistance of the cell is, then

A voltmeter has resistance of 2000 ohms and it can measure upto 2V. If we want to increase its range to 10 V, then the required resistance in series will be

AB is a wire of uniform resistance. The galvanometer G shows no current when the length AC = 20cm and CB = 80 cm. The resistance R is equal to

An ammeter with internal resistance 90 Ω reads 1.85 A when connected in a circuit containing a battery and two resistors 700 Ω and 410 Ω in series. Actual current will be

Which of the following is correct

For comparing the e.m.f.'s of two cells with a potentiometer, a standard cell is used to develop a potential gradient along the wires. Which of the following possibilities would make the experiment unsuccessful

A voltmeter having a resistance of 998 ohms is connected to a cell of e.m.f. 2 volt and internal resistance 2 ohm. The error in the measurement of e.m.f. will be

Which is a wrong statement

The resistance of a galvanometer is 25 ohm and it requires 50μA for full deflection. The value of the shunt resistance required to convert it into an ammeter of 5 amp is

In a potentiometer circuit there is a cell of e.m.f. 2 volt, a resistance of 5 ohm and a wire of uniform thickness of length 1000 cm and resistance 15 ohm. The potential gradient in the wire is

A galvanometer of resistance 25 Ω gives full scale deflection for a current of 10 milliampere, is to be changed into a voltmeter of range 100 V by connecting a resistance of ‘R’ in series with galvanometer. The value of resistance R in Ω is

The current flowing through a coil of resistance 900 ohms is to be reduced by 90%. What value of shunt should be connected across the coil

50 Ω and 100 Ω resistors are connected in series. This connection is connected with a battery of 2.4 volts. When a voltmeter of 100 Ω resistance is connected across 100 Ω resistor, then the reading of the voltmeter will be

A 2 volt battery, a 15 Ω resistor and a potentiometer of 100 cm length, all are connected in series. If the resistance of potentiometer wire is 5 Ω, then the potential gradient of the potentiometer wire is

In the diagram shown, the reading of voltmeter is 20 V and that of ammeter is 4 A. The value of R should be (Consider given ammeter and voltmeter are not ideal)

Which of the following statement is wrong

A voltmeter has a resistance of G ohms and range V volts. The value of resistance used in series to convert it into a voltmeter of range nV volts is

Two cells when connected in series are balanced on 8m on a potentiometer. If the cells are connected with polarities of one of the cell is reversed, they balance on 2m. The ratio of e.m.f.'s of the two cells is

The resistance of a galvanometer is 90 ohms. If only 10 percent of the main current may flow through the galvanometer, in which way and of what value, a resistor is to be used

If in the experiment of Wheatstone's bridge, the positions of cells and galvanometer are interchanged, then balance points will

In the experiment of potentiometer, at balance, there is no current in the

If the length of potentiometer wire is increased, then the length of the previously obtained balance point will

In the Wheatstone's bridge (shown in figure) X = Y and A > B. The direction of the current between ab will be

In an experiment of meter bridge, a null point is obtained at the centre of the bridge wire. When a resistance of 10 ohm is connected in one gap, the value of resistance in other gap is

Potential gradient is defined as

A galvanometer of 10 ohm resistance gives full scale deflection with 0.01 ampere of current. It is to be converted into an ammeter for measuring 10 ampere current. The value of shunt resistance required will be 

A battery of 6 volts is connected to the terminals of a three metre long wire of uniform thickness and resistance of the order of 100 Ω. The difference of potential between two points separated by 50 cm on the wire will be