The fact that electric charges are integral multiples of the fundamental electronic charge was proved experimentally by 
(1) Planck                   

(2) J.J. Thomson

(3) Einstein                 

(4) Millikan

Subtopic:  Various Atomic Models |
 57%
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 narrow electron beam passes undeviated through an electric field E = 3×104 volt/m and an overlapping magnetic field B=2×10-3 Weber/m2. If electric field and magnetic field are mutually perpendicular. The speed of the electrons is 
1. \(60\) m/s                       
2. 10.3×107 m/s
3. 1.5×107 m/s             
4. 0.67×10-7 m/s

Subtopic:  Lorentz Force |
 89%
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 specific charge of an electron is 

(a) 1.6×10-19 coulomb

(b) 4.8×10-10 stat coulomb

(c) 1.76×1011 coulomb/kg

(d) 1.76×10-11  coulomb/kg

Subtopic:  Various Atomic Models |
 54%
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

advertisementadvertisement

Cathode rays are similar to visible light rays in that

(1) They both can be deflected by electric and magnetic fields

(2) They both have a definite magnitude of wavelength

(3) They both can ionize a gas through which they pass

(4) They both can expose a photographic plate

Subtopic:  Photoelectric Effect: Experiment |
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 beam of electrons is moving with constant velocity in a region having electric and magnetic fields of strength 20 Vm-1 and 0.5 T at right angles to the direction of motion of the electrons. What is the velocity of the electrons

1. 20 ms-1                  2. 40 ms-1 
3. 8 ms-1                    4. 5.5 ms-1

Subtopic:  Lorentz Force |
 92%
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

Electron volt is a unit of 
(1) Potential                         

(2) Charge

(3) Power                             

(4) Energy

Subtopic:  Electron Emission |
 73%
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

advertisementadvertisement

The ratio of specific charge of an α-particle to that of a proton is 
(1) 2 : 1                     

(2) 1 : 1

(3) 1 : 2                     

(4) 1 : 3

Subtopic:  Various Atomic Models |
 64%
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

In Bainbridge mass spectrograph a potential difference of 1000 V is applied between two plates distant 1 cm apart and magnetic field in B = 1T. The velocity of undeflected positive ions in m/s from the velocity selector is

(1)107 m/s                    

(2) 104 m/s

(3) 105 m/s                   

(4) 102 m/s 

Subtopic:  Lorentz Force |
 73%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

Order of q/m ratio of proton, α-particle and electron is

(a) e>p>α               (b) p>α>e

(c) e>α>p               (d) None of these

Subtopic:  Lorentz Force |
 73%
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

advertisementadvertisement

O++, C+, He++ and H+ ions are projected on the photographic plate with the same velocity in a mass spectrograph. Which one will strike the farthest?
1. O++
2. C+
3. He++
4. H+

Subtopic:  Lorentz Force |
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