Q13.An electron is moving along +x direction with a velocity of 6 × 106 ms−1 . It enters a region of uniform electric field of 300 V /cm pointing along +y direction. The magnitude and direction of the magnetic field set up in this region such that the electron keeps moving along the x direction will be: (1) 3 × 10−4T, along +z direction (2) 5 × 10−3T, along −z direction (3) 5 × 10−3T, along +z direction (4) 3 × 10−4T, along −zdirection JEE Main 2020 (06 Sep Shift 1) JEE Main Previous Year Paper
What This Question Tests
This problem is a classic application of the velocity selector principle, where electric and magnetic forces on a charged particle balance each other, requiring vector analysis to find the magnetic field's direction.
Concepts Tested
Formulas Used
F_e = qE
F_m = q(v x B)
F_e + F_m = 0
📚 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?
4.6 — A 3.0 Cm Wire Carrying A Current Of 10 A Is Placed Inside A Solenoid
Physics Class 11 · Chapter 4
4.6 A 3.0 cm wire carrying a current of 10 A is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 0.27 T. What is the magnetic force on the wire?
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Velocity Selector
- Year
- 2020
- Shift
- 06 Sep Shift 1
- Q Number
- Q13
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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