HARD

Earn 100

Give comment on the IV curve of the filament at high and low voltage curve.

Important Questions on Resistance and Resistivity

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

The resistivity of potentiometer wire is

40 \times 10^{- 8} Ω m

and its area of cross-section is

8 \times 10^{- 6} m^{2}

. If

0.2 A

current is flowing through the wire, the potential gradient of the wire is

HARD

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

An incandescent bulb has a thin filament of tungsten that is heated to high temperature by passing an electric current. The hot filament emits black-body radiation. The filament is observed to break up at random locations after a sufficiently long time of operation due to non-uniform evaporation of tungsten from the filament. If the bulb is powered at constant voltage, which of the following statement(s) is(are) true?

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

In the circuit shown, the cells

A

and

B

have negligible resistances for

V_{A} = 12 V, R_{1} = 500 Ω

and

R = 100 Ω

. The galvanometer

(G)

shows no deflection. The value of

V_{B}

HARD

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

A voltmeter having a resistance of

900 Ω

is used to measure the potential difference across a

100 Ω

resistor which is connected to a battery of emf

150 V

and internal resistance

10 Ω .

The percentage of decrease in the potential difference across the

100 Ω

resistor when the voltmeter is connected across it is

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

A circuit to verify Ohm's law uses ammeter and voltmeter in series or parallel connected corrected correctly to the resistor. In the circuit :

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

Find the potential difference between $a$ and $b$ , as shown in the below circuit.

Question Image

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

An ideal ammeter is connected to a battery as shown in the figure. The currents through the $5.0 Ω$ resistor and the $2.0 Ω$ resistor are, respectively

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EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

In the figure shown, what is the current (in ampere) drawn from the battery? You are given:
$R_{1} = 15 Ω, R_{2} = 10 Ω, R_{3} = 20 Ω, R_{4} = 5 Ω, R_{5} = 25 Ω, R_{6} = 30 Ω, E = 15 V$
Question Image

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

Ohm's law is applicable to

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

The current in a simple series circuit is

5.0 A

. When an additional resistance of

2.0 Ω

is inserted, the current drops to

4.0 A

. The original resistance of the circuit (in

Ω

) was

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

A potential difference

16 V

is established across an electrolytic solution. It is found that

1.5 \times 10^{16}

divalent positive ions move towards cathode per second and

2 \times 10^{16}

monovalent negative ions move towards the anode per second. The resistance of the electrolytic solution is:

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

Three conductors draw currents of

1 A, 2 A & 4 A

, respectively when connected in turn across a battery. If they are connected in series across the same battery, the current drawn will be

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

A cell of emf

E

is connected across a resistance

R .

The potential difference between the terminals of the cell is found to be

V .

The internal resistance of the cell must be

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

A cell of emf

e

and internal resistance

r

is put across a variable resistor of zero to

R

V and I

are potential difference and current through variable resistor. The VI curve indicates that
Question Image

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

In the circuit shown below, the ammeter reading is zero. The value of the resistance

R

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

Which of the following is the most likely temperature of the filament of an electric light bulb when it is working on the normal

220 V

supply line ?

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

Two similar cells, whether joined in series or in parallel, have the same current through an external resistance of

2 Ω

. The internal resistance of each cell is .................

EASY

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

In a filament type light bulb, most of the electric power consumed appears as:

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

A wire of length

100 c m

is connected to a cell of emf

2 V

and negligible internal resistance. The resistance of the wire is

3 Ω,

the additional resistance required to produce a potential difference of

1 m V / c m

MEDIUM

Physics>Current Electricity>Resistance and Resistivity>Ohm's Law

Two batteries of emf $4 V$ and $8 V$ with internal resistance $1 Ω$ and $2 Ω$ are connected in a circuit with a resistance of $9 Ω$ as shown in figure. The current and potential difference between the points $P$ and $Q$ are
Question Image

Give comment on the IV curve of the filament at high and low voltage curve.

Important Questions on Resistance and Resistivity

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