In a physics laboratory experiment, a coil with 180 turns. Each turn of the coil encloses an area of 12 cm2 . The coil is rotated 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 rotation takes 3.4×10−2 s . The earth's magnetic field at the location of the laboratory is 6.0×10−5 T.

A) What is the magnetic flux through one turn of the coil before it is rotated? The SI unit for magnetic flux is the Weber (Wb), which is equal to Tm^2.
B) What is the magnetic flux through one turn of the coil after it is rotated?
C) What is the average emf induced in the coil as it is rotated from the perpendicular to the parallel orientation?

A) Φ_i = 7.2 x 10^(-8) Wb

B) Φ_f = 0 Wb

C) EMF = 0.381 mV

Explanation:

We are given;

Area; A = 12 cm² = 12 x 10^(-4) m²

Magnetic Field; B = 6 x 10^(-5) T

Rotation time; t = 3.4×10^(-2) s = 0.034s

A) Magnetic flux is given by the equation;

Φ = BA•cosθ

Where;

B is the magnetic field

A is area

θ is angle to magnetic field

Now, at initial point where its plane is perpendicular to the earth's magnetic field, the angle is 0

Thus,

Φ_i = BA•cosθ = 6 x 10^(-5) x 12 x 10^(-4) x cos(0)

Φ_i = 7.2 x 10^(-8) Wb

B) Now, the coil is rotated to a place where its plane is parallel to the earth's magnetic field and thus, the angle here is 90°

Thus,

Φ_f = BA•cosθ = 6 x 10^(-5) x 12 x 10^(-4) x cos(90) = 0 Wb

C) The formula for average EMF induced is given by;

EMF = N[(Φ_f - Φ_i)/t]

Where N is number of turns, t is time while Φ_f and Φ_i have been calculated earlier.

Thus,

EMF = 180[(0 - 7.2 x 10^(-8))/0.034]

EMF = 180[(-7.2 x 10^(-8)/0.034]

EMF = - 3.81 x 10^(-4) V or - 0.381 mV

We want magnitude of the EMF, thus we will take absolute value of the EMF, so, we'll use;

EMF = 0.381 mV

Φθ

relativism, roughly put, is the view that truth and falsity, right and wrong, standards of reasoning, and procedures of justification are products of differing conventions and frameworks of assessment and that their authority is confined to the context giving rise to them. more precisely, “relativism” covers views which maintain that—at a high level of abstraction—at least some class of things have the properties they have (e.g., beautiful, morally good, epistemically justified) not simpliciter, but only relative to a given framework of assessment (e.g., local cultural norms, individual standards), and correspondingly, that the truth of claims attributing these properties holds only once the relevant framework of assessment is specified or supplied. relativists characteristically insist, furthermore, that if something is only relatively so, then there can be no framework-independent vantage point from which the matter of whether the thing in question is so can be established.

relativism has been, in its various guises, both one of the most popular and most reviled philosophical doctrines of our time. defenders see it as a harbinger of tolerance and the only ethical and epistemic stance worthy of the open-minded and tolerant. detractors dismiss it for its alleged incoherence and uncritical intellectual permissiveness. debates about relativism permeate the whole spectrum of philosophical sub-disciplines. from ethics to epistemology, science to religion, political theory to ontology, theories of meaning and even logic, philosophy has felt the need to respond to this heady and seemingly subversive idea. discussions of relativism often also invoke considerations relevant to the very nature and methodology of philosophy and to the division between the so-called “analytic and continental” camps in philosophy. and yet, despite a long history of debate going back to plato and an increasingly large body of writing, it is still difficult to come to an agreed definition of what, at its core, relativism is, and what philosophical import it has. this entry attempts to provide a broad account of the many ways in which “relativism” has been defined, explained, defended and criticized.

explanation:

true tan speed = ang vel x radius