Answer:
Explanation:
Given,
Magnetic field
Radius
The angle between the area vector and magnetic field is 0 degree, because the direction of area vector is always perpendicular to the plane.
Answer:
37.5 Seconds
Explanation:
Speed = frequency * Wavelength
We can find the Frequency by the information given, Frequency = waves per second .
40 Waves per second, = 40 Hz
Wavelength = 8cm
Cm = M
8cm/100 = 0.08m
Speed = 40 Hz * 0.08m
Speed = 3.2m/s
Speed = Distance / time taken
Time = Distance / Speed
Time = 120 / 3.2
Time = 37.5 seconds
The answer is the bottom one, all of the above