Electrons contribute charge and mass to the atom. a. negative, a lot of b. little, a lot of c. negative, little

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Which notation is used to represent an alpha particle? a. b. c. d.

The charge on an electron is 1.60218 × 10−19 c and its mass is 9.10939 × 10−31 kg. how strong a magnetic field must be experienced by the electron if its path is a circle of radius 5.5 cm? answer in units of t.