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 $$= 1.6 \times 10^{-19}$$ C; Mass of the electron $$= 9.1 \times 10^{-31}$$ kg]

A

$$7.5 \times 10^{-3}$$ m

B

$$7.5 \times 10^{-2}$$ m

C

7.5 m

D

$$7.5 \times 10^{-4}$$ m