Answer:
Time will be 19 ms so option (a) is correct option
Explanation:
We have given that mass of wire m = 50 gram = 0.5 kg
Frequency f = 810 Hz
Wavelength = 0.4 m
Velocity is given by

Amplitude is given as d = 6 m
So time 
So option (a) is correct option
Answer should be the earth
Answer: 0.091 m
Explanation:
r = 1/B * √(2mV/e), where
r = radius of their circular path
B = magnitude of magnetic field = 1.29 T
m = mass of Uranium -238 ion = 238 * amu = 238 * 1.6*10^-27 kg
V = potential difference = 2.9 kV
e = charge of the Uranium -238 ion = 1.6*10^-19 C
r = 1/1.29 * √[(2 * 238 * 1.6*10^-27 * 2900) / 1.6*10^-19]
r = 1/1.29 * √(2.21*10^-21 / 1.6*10^-19)
r = 1/1.29 * √0.0138
r = 1/1.29 * 0.117
r = 0.091 m
Therefore, the radius of their circular path is 0.091 m
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