7.5 x 10⁻¹¹m. An electromagnetic wave of frecuency 4.0 x 10¹⁸Hz has a wavelength of 7.5 x 10⁻¹¹m.
Wavelength is the distance traveled by a periodic disturbance that propagates through a medium in a certain time interval. The wavelength, also known as the space period, is the inverse of the frequency. The wavelength is usually represented by the Greek letter λ.
λ = v/f. Where v is the speed of propagation of the wave, and "f" is the frequency.
An electromagnetic wave has a frecuency of 4.0 x 10 ¹⁸Hz and the speed of light is 3.0 x 10⁸ m/s. So:
λ = (3.0 x 10⁸ m/s)/(4.0 x 10¹⁸ Hz)
λ = 7.5 x 10⁻¹¹m
The central force acting on the electron as it revolves in a circular orbit is
.
The given parameters;
- <em>speed of electron, v = 2.2 x 10⁶ m/s</em>
- <em>radius of the circle, r = 4.63 x 10⁻¹¹ m</em>
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The central force acting on the electron as it revolves in a circular orbit is calculated as follows;

where;
is mass of electron = 9.11 x 10⁻³¹ kg

Thus, the central force acting on the electron as it revolves in a circular orbit is
.
Learn more about centripetal force here:brainly.com/question/20905151
His knees are flat in front of him or 180 degrees, i hope that answered your question
Mirrors reflect meaning shows what would be seen if everything was turned around, therefore, it shows text backwards because if it is turned around, it is in reverse order.
Answer:
Short answer, because copper wire does not have high resistance.
Explanation: