# A battery has e.m.f. 4 V and internal resistance r. When this battery is connected to an external resistance of 2 ohm, a current of 1 ampere flows in the circuit. How much current will flow if the terminals of the battery are connected directly? 1. 1 A 2. 2 A 3. 4 A 4. Infinite

Subtopic:  EMF & Terminal Voltage |
66%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The current I as shown in the circuit will be:

1.  10 A

2.  $\frac{20}{3}$ $\mathrm{A}$ 

3.  $\frac{2}{3}$ $\mathrm{A}$  

4.  $\frac{5}{3}$ $\mathrm{A}$

Subtopic:  Combination of Resistors |
60%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A meter bridge is set up to determine unknown resistance x using a standard 10 $\Omega$ resistor. The galvanometer shows the null point when the tapping key is at a 52 cm mark. End corrections are 1 cm and 2 cm respectively for end A and B. Then the value of x is:

1.  10.2 $\Omega$

2.  10.6 $\Omega$

3.  10.8 $\Omega$

3. 11.1 $\Omega$

Subtopic:  Meter Bridge & Potentiometer |
52%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The resistivity of iron is 1 × 10–7 ohm m. The resistance of iron wire of particular length and thickness is 1 ohm. If the length and the diameter of wire both are doubled, then the resistivity in ohm m will be :

(1) 1 × 10–7

(2) 2 × 10–7

(3) 4 × 10–7

(4) 8 × 10–7

Subtopic:  Derivation of Ohm's Law |
67%
From NCERT
PMT - 1983
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The resistivity of a wire :

 1 Increases with the length of the wire 2 Decreases with the area of cross-section 3 Decreases with the length and increases with the cross-section of the wire 4 None of the above statement is correct
Subtopic:  Derivation of Ohm's Law |
73%
From NCERT
PMT - 1984
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Drift velocity vd varies with the intensity of electric field as per the relation:

1. ${v}_{d}\propto E$

2. ${v}_{d}\propto \frac{1}{E}$

3. vd = constant

4. ${v}_{d}\propto {E}^{2}$

Subtopic:  Current & Current Density |
77%
From NCERT
PMT - 1981
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

In a conductor 4 coulombs of charge flows for 2 seconds. The value of electric current will be :

(1) 4 volts

(2) 4 amperes

(3) 2 amperes

(4) 2 volts

Subtopic:  Current & Current Density |
90%
From NCERT
PMT - 1984
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The specific resistance of a wire is ρ, its volume is 3 m3 and its resistance is 3 ohms, then its length will be

(1) $\sqrt{\frac{1}{\rho }}$

(2) $\frac{3}{\sqrt{\rho }}$

(3) $\frac{1}{\rho }\sqrt{3}$

(4) $\rho \sqrt{\frac{1}{3}}$

Subtopic:  Derivation of Ohm's Law |
80%
From NCERT
PMT - 1984
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

When a piece of aluminum wire of finite length is drawn through a series of dies to reduce its diameter to half its original value, its resistance will become :

(1) Two times

(2) Four times

(3) Eight times

(4) Sixteen times

Subtopic:  Derivation of Ohm's Law |
From NCERT
AIIMS - 2002
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Through a semiconductor, an electric current is due to drift off:

(1) Free electrons

(2) Free electrons and holes

(3) Positive and negative ions

(4) Protons

Subtopic:  Current & Current Density |
74%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch