Q21.The velocity of certain ions that pass undeflected through crossed electric field E = 7.7kV/m and magnetic field B = 0.14 T is (1) 18 km/s (2) 77 km/s (3) 55 km/s (4) 1078 km/s
What This Question Tests
This problem directly applies the principle of a velocity selector where the electric and magnetic forces on a charged particle balance out.
Concepts Tested
Formulas Used
F_e = qE
F_m = qvB
v = E/B
📚 NCERT Sections This Tests
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?
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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)
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📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Velocity selector
- Year
- 2012
- Shift
- 07 May Online
- Q Number
- Q21
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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