Suppose a 58-turn coil lies in the plane of the page in a uniform magnetic field that is directed out of the page. The coil originally has an area of 0.175 m2. It is stretched to have no area in 0.100 s. What is the magnitude (in V) and direction (as seen from above) of the average induced emf if the uniform magnetic field has a strength of 1.60 T?

Magnitude of the induced emf = 162,4 volts

The induced emf is directed into the page (i.e. from top to bottom)

Explanation:

Strength of the magnetic field, B = 1.60 T

Number of turns in the coil, N = 58

Initial Area of the coil, A₁ = 0.175 m²

Final Area of the coil, A₂ = 0

change in time, Δt = 0.1 s

Change in Magnetic flux, Δ∅ = B(A₂ - A₁)

∅ = 1.6 * (0-0.175)

∅ = -0.28 wb

Induced emf, V = (NΔ∅)/Δt

V = (-58*0.28)/0.1

V = -162 .4 volts

Magnitude of V = 162.4 V

The induced emf is directed into the page ( From top to bottom)

the higher the current the higher the mag field around it the higher the influence on the compass