Physics-
General
Easy
Question
An electron (mass = 9× 10–31kg. Charge = 1.6 × 10–19C) whose kinetic energy is 7.2 × 10–18 joule is moving in a circular orbit in a magnetic field of 9 × 10–5 weber/m2. The radius of the orbit is
- 1.25 cm
- 2.5 cm
- 12.5 cm
- 25.0 cm
The correct answer is: 25.0 cm
= 0.25 m = 25 cm
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