What is true about the refractive index of a medium?
a.
it increases with an increase in angle of incidence.
b.
it decreases with a decrease in angle of refraction.
c.
it decreases with an increase in angle of incidence.
d.
it is independent of any change in angle of incidence or angle of refraction.
e.
it increases with a decrease in angle of refraction.

D. It is independent of any change in angle of incidence or angle of refraction.

car a and b are moving in opposite directions

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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: