1) am radio waves
The lowest and highest frequencies of the radio signals are:
The speed of the waves is the speed of light,
, so to find the corresponding wavelengths we can use the basic relationship between frequency, wavelength and speed of a wave:
where f is the frequency and
the wavelength.
The wavelength corresponding to the lowest frequency is:
while the wavelength corresponding to the highest frequency is
So, the range of wavelengths is [187.5-545] m.
2) fm radio waves
This time, the lowest and highest frequencies of the radio waves are:
So the corresponding wavelengths are:
Therefore, the range of wavelengths of the rm radio signals is [2.8-3.4] m.
Distance= Time×Speed
= 1800×1.5
= 2700 m
I am not sure it's right. the question itself is confusing.
Answer: A)
Explanation: when an electron is placed in a magnetic field, it experiences a force.
This force is given below as
F=qvB*sinθ
F = force experienced by charge.
q = magnitude of electronic charge
v = speed of electron
B= strength of magnetic field
θ = angle between magnetic field and velocity.
What defines the force exerted on the charge is the angle between the field and it velocity.
If magnetic field is parallel to velocity, then it means that θ=0° which means sin 0 = 0, which means
F = qvB * 0 = 0.
The charge being at rest has nothing to do with the angle between magnetic field strength and velocity.
Increasing the separation distance between objects decreases the force of attraction or repulsion between the objects. And decreasing the separation distance between objects increases the force of attraction or repulsion between the objects. Electrical forces are extremely sensitive to distance.