Americas
Europe
Q14P
Expert-verifiedIn Figure (a), a uniform magnetic field increases in magnitude with time t as given by Figure (b), where the vertical axis scale is set by and the horizontal scale is set by A circular conducting loop of area lies in the field, in the plane of the page. The amount of charge q passing point A on the loop is given in Figure (c) as a function of t, with the vertical axis scale set by and the horizontal axis scale again set by localid="1661854094654" . What is the loop’s resistance?
Resistance of the loop is, R =
Calculate the induced emf by using the slope of the line form Fig. 30-42(b) in Faraday’s law. Find the current by finding the slope of the line from Fig.30-42 (c) to find the resistance of the loop by using Ohm’s law.
Faraday's law of electromagnetic induction states, Whenever a conductor is placed in a varying magnetic field, an electromotive force is induced in it.
Ohm's law states that the voltage across a conductor is directly proportional to the current flowing through it, provided all physical conditions and temperatures remain constant.
Formulae are as follow:
Where, is magnetic flux, dt is time, dq is charge, i is current, R is resistance, 𝜀 is emf,
First, find the emf by using Faraday’s law.
From Fig.30 - 42 (b) the slope of the line i.e. dB/dt can be found as,
Faraday’s law is given as,
As magnetic field is perpendicular to the area vector,
Therefore,
role="math" localid="1661853786477"
Substituting the values,
Now, the current can be calculated from Fig. 30- 42 (c).
The slope of the graph gives dq/dt.
Therefore,
Now, relate the induced emf to resistance and current by using Ohm’s law.
Substituting the values,
Hence, resistance of the loop is,
Therefore, we calculated the resistance of the loop by using the slopes from the graph, Faraday’s law, and Ohm’s law.
94% of StudySmarter users get better grades.
Sign up for free