Which of the following factors could you change in a system and not change its induced emf?
a.
magnetic field
b.
type of wire
c.
velocity of the wire
d.
length of the wire in the field

The type of wire

Explanation:

The EMF is induced in the closed conducting loop whenever there is a change in the magnetic flux linked with it. Mathematically, it is given by :

Where

is the magnetic flux

         

For n number of coils,

Where

B is the magnetic field

A is the area of the coil

If the coil is moved with the speed of v in the magnetic field, then induced EMF is given by :

l is the length of the coil

So, the induced EMF depends on the following factors:

magnetic fieldvelocity of the wirelength of the wire in the field

So, the type of wire do not change the induced emf of the coil. Hence, the correct option is (b).

Answer: a charge of -1.0  × 10⁻⁴ c must be placed  at x = 26 m.the sign of the charge will be the same sign as the  -4.0  µc charge.======electricstatic force between two point charges  is given by    where k is coulomb's constant,  8.99×10⁹  n·m²/c², q₁ and q₂ are the point charges, and r is the distance between the two point charges.assign positive to q₁let q₁ =  6.0 µc, q₂ = -4.0  µc, q₀ represent the charge at the origin, and q₃ represent this new charge to place.the charge at the origin q₀ would experience the following force f₀₁ from q₁, with r = 6.0 m (note that 1  µc = 10⁻⁶ c)    the force from q₂    the force from q₃    the net force on the origin charge, q₀, has to be zero for no electrostatic forcehaving an equation where k and q₀ can be divided out of the equation will allow us to solve for q₃    isolating:     a charge of -1.0  × 10⁻⁴ c must be placed  at x = 26 m.the sign of the charge will be the same as the  -4.0  µc charge

Iwould think it is temperature, silica, oxides (gases)