You have a rectangular solid. you would like to pass current through it so that it has the least resistance. should you direct the current perpendicular to side a, b, or c? explain. b: in a different experiment, current is passed through side a (and out the opposite side). use 0.2m×0.1m×0.02m for the dimensions of the solid and assume that the solid is made of copper so its resistivity is rho = 1.69×10−8 ωm and ne− = 8.49×1028 e−/m3. the potential difference across the solid is maintained at 0.001 v. determine the drift velocity of the electrons and then how long it would take a single electron to pass completely through the copper.

a) we know that resistance is directly proportional to the length of the conductor as length increases the resistance also increases so to direct the current with least resistance, then the direction is perpendicular to side B only other sides have a larger length than B.

b) = 4.35 × 10⁻⁴ m/s

time = 229.56 s

Explanation:

Given:

a) we know that resistance is directly proportional to the length of the conductor as length increases the resistance also increases so to direct the current with least resistance, then the direction is perpendicular to side B only other sides have a larger length than B.

Dimension =  0.2m × 0.1m × 0.02m

ρ = 1.69×10⁻⁸ Ωm

= 8.49 × 10²⁸ e−/m³

Potential difference across the solid = 0.001 V

Now,

from Ohm's law V = I × R

here

V is potential difference

I is the current

R is the resistance

or

R =

also,

R =

Here, l is the length

A is the area

and,

the drift speed, =

substituting value of I in the above equation, we get

=

on substituting the values, we get

or

= 4.35 × 10⁻⁴ m/s

also,

the time taken, t =

=

= 229.56 s

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation: