Q19.In an experiment, electrons are accelerated, from rest, by applying a voltage of 500 V . Calculate the radius of the path if a magnetic field 100mT is then applied. [Charge of the electron = 1.6 × 10−19C Mass of the electron = 9.1 × 10−31 kg] (1) 7.5 × 10−3 m (2) 7.5 × 10−2 m (3) 7.5 m (4) 7.5 × 10−4 m
What This Question Tests
This question combines the acceleration of an electron by an electric potential with its subsequent circular motion in a magnetic field to calculate the radius of the path.
Concepts Tested
Formulas Used
qV = (1/2)mv^2
qvB = mv^2/r
r = mv/qB
📚 NCERT Sections This Tests
4.11 — In A Chamber, A Uniform Magnetic Field Of 6.5 G (1 G = 10–4 T) Is
Physics Class 11 · Chapter 4
4.11 In a chamber, a uniform magnetic field of 6.5 G (1 G = 10–4 T) is maintained. An electron is shot into the field with a speed of 4.8 × 106 m s–1 normal to the field. Explain why the path of the electron is a circle. Determine the radius of the circular orbit. (e = 1.5 × 10–19 C, me = 9.1×10–31 kg)
4.4 — A Horizontal Overhead Power Line Carries A Current Of 90 A In East To
Physics Class 11 · Chapter 4
4.4 A horizontal overhead power line carries a current of 90 A in east to west direction. What is the magnitude and direction of the magnetic field due to the current 1.5 m below the line?
11.3 — The Photoelectric Cut-Off Voltage In A Certain Experiment Is 1.5 V.
Physics Class 12 · Chapter 11
11.3 The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Motion of charged particles in magnetic fields
- Year
- 2019
- Shift
- 11 Jan Shift 1
- Q Number
- Q19
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Magnetic Effects of Current
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