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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 100 mT is then applied. [Charge of the electron = 1.6 × 10 –19 C Mass of the electron = 9.1 × 10 –31 kg]

1. 7.5 × 10 –4 m
2. 7.5 × 10 –3 m
3. 7.5 m
4. 7.5 × 10 –2 m

Correct answer: 7.5 × 10 –4 m

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