Answer:
1.85 x 10^10 cycles per second
Explanation:
B = 0.66 T, theta = 90 degree, q = 1.6 x 10^-19 C,
The time period of electron is given by
T = 2 π m / B q
Frequency is teh reciprocal of time period.
f = 1 /T
f = B q / (2 π m)
f = (0.66 x 1.6 x 10^-19) / (2 x 3.14 x 9.1 x 10^-31)
f = 1.85 x 10^10 cycles per second