Calculate the skin-depth of a plane electromagnetic wave of frequency 50 hz in copper sheet wire of conductivity 5.8 10' (per ohm-m) and relative magnetic permeability b. in wires with diameter much greater than the skin-depth, ac currents locate near to the surface. how thick can a copper wire carrying 50hz currents usefully be, assuming the amplitude at the centre of the wire is double that calculated from plane-wave attenuation and skin depth? [this "doubling" arises because the field can penetrate from two directions rather than from just one]. define your criterion for "useful". c. calculate the skin-depth of a plane electromagnetic wave of frequency 60 hz in amorphous cobalt magnetic shielding wire of conductivity 7*10 (per ohm-m) and relative magnetic permeability 1,000,000 d. how thick would the walls of a shielded roomm made out of copper have to be to reduce the internal powerline noise field to 1 part per million of its external value? e. how thick would the walls need to be using amorphous cobalt shielding?

do you have a formula possibly

we're given that v₀ = 0 and a = 5.4 m/s². therefore, since v = at + v₀ for constant acceleration the equation for velocity is

after 28s,

m/s

which i would round to 150 m/s as my final answer

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.