Answer:
Yes,in fact visible 'light' is a form of radiation, which can be defined as an energy that travels in the form of electromagnetic waves. It can also be described as a flow of particle-like 'wave-packets', called photons, that travel constantly at the speed of light (about 300 000 kilometres per second).
Explanation:
Answer: the minimal force that you need to apply to move the bureau is F = 198.45N
Explanation:
If you want to move an object, you need to apply a force that is bigger than the force of the statical friction.
The force of statical friction can be written as.
Ff = k*N
where k is the coefficient of static friction, in this case, k = 0.45, and N is the normal force between the object and the surface.
In this case, the normal force is the weight of the bedroom bureau, this is:
N = m*g = 45kg*9.8m/s^2 = 441N
Then the force is:
Fr = 0.45*441N = 198.45N
This means that the minimal force that you need to apply to move the bureau is F = 198.45N
and after this point, the force of friction will work wit the kinetic coefficient of friction, that usually is smaller than the statical one.
Answer: The complexity of filter is the order of the filter. Greater the order of the filter, more efficient the filter is. Roll of value of one filter is 20dB/dec. So the roll-off value of 8th order filter is 160dB/dec. 8th order filter is more efficient than the second order low-pass filter.