If the desk doesn't move, then it's not accelerating.
If it's not accelerating, then the net force on it is zero.
If the net force on it is zero, then any forces on it are balanced.
If there are only two forces on it and they're balanced, then they have equal strengths, and they point in opposite directions.
So the friction on the desk must be equal to your<em> 245N</em> .
Answer:
a

b

Explanation:
From the question we are told that
Their distance apart is 
The wavelength of each source wave 
Let the distance from source A where the construct interference occurred be z
Generally the path difference for constructive interference is

Now given that we are considering just the straight line (i.e points along the line connecting the two sources ) then the order of the maxima m = 0
so

=> 
=> 
Generally the path difference for destructive interference is

=> 
=> 
substituting values

=> 
So


and

=> 
=> 
Answer:
None
Explanation:
Subatomic particles are the particles which are very smaller than the atoms. Elementary particles are the examples of subatomic particles.
Elementary particles are the particles without any sub-structure which means they are not composed of other particles.
The elementary particles are classified into three categories which are discussed below:
(1) Quarks: up, down, top, bottom, strange, and charm.
(2) Leptons: muon, muon neutrino, electrons, electron neutrino, tau, tau neutrino.
(3) Bosons: Z bosons, W bosons, Higgs, Gluon, photons.
Mesons are the particles which compose one quark and one anti quarks.
Therefore, in the given list there is no meson.
Magnetic field is the magnetic effect of electric currents and magnetic materials. The magnetic field at any given point specified by both direction and a magnitude. So uniform magnetic field has equal amount of force or magnetic force in both side of the object while the non uniform magnetic field has one of the object exert more than the other