Question

Part A In a physics laboratory experiment, a coil with 240 turns enclosing an area of 14.0 cm2 is rotated in a time interval of 4.70x10-2 s from a position where its plane is perpendicular to the earth's magnetic field to one where its plane is parallel to the field. The earth's magnetic field at the lab location is 5.7x10-5 T. What is the magnetic flux through each turn of the coil before it is rotated? Express your answer using two significant figures. % ADO A O O ? = Wb Submit Request Answer Part B What is the magnetic flux through each turn of the coil after it is rotated? Express your answer using two significant figures. 190 AZC RO O ? I wb Submit Request Answer Part C What is the average emf induced in the coil? Express your answer using two significant figures. %AED + R o B ?

Answer 1

Number of turns N = 240

Area of cross section of the coil A = 14 cm² = 14$\times$10^-4 m²

Earth's magnetic field B = 5.7$\times$10^-5 T

Time interval t = 4.7$\times$10^-2 s

A) Before the rotation , the magnetic field is perpendicular to the plane of the coil , angle between the magnetic field and normal to the plane of the coil $\theta$ ₁ = 0 degree

Magnetic flux $\phi$ ₁ = NBAcos$\theta$₁

$\phi$₁ = 240$\times$5.7$\times$10^-5$\times$14$\times$10^-4$\times$cos0

$\phi$₁ = 19.15$\times$10^-6 Wb

B) After rotation of the coil the plane of the coil is parallel to the earth's magnetic field , angle between the magnetic field and normal to the plane of the coil is 90 degree.

Magnetic flux $\phi$ ₂ = NBAcos90

$\phi$₂ = 0 Wb

C) Average emf induced in the coil

E = - ($\phi$₂ - $\phi$ ₁)/t

E = - ( 0 - 19.15$\times$10^-6) / 4.7$\times$ 10^-2

E = 4.074 $\times$ 10^-4 V