Physics 9702 · AS & A Level · Electromagnetic induction

Electromagnetic induction — practice question

(a)[2]

What does magnetic flux mean?

(b)

The wire coil is square, has side length $12\,\text{cm}$, and contains $8$ insulated turns. It is stationary in a uniform magnetic field. As shown in Fig. 6.1, the plane of the coil is perpendicular to the magnetic field. The magnetic flux density $B$ changes with time $t$ as shown in Fig. 6.2.

(b(i))[3]

Find the magnetic flux linkage in the coil at $t = 0.60\,\text{s}$. Include the unit in your response.

(b(ii))[1]

State how Fig. 6.2 shows that the electromotive force (e.m.f.) $E$ induced across the terminals between $t = 0$ and $t = 0.60\,\text{s}$ remains constant.

(b(iii))[2]

Calculate the size of $E$.

(c)[3]

In part (b), the process is carried out again, but now the coil terminals are connected together. State and explain what happens to the coil when the magnetic flux density changes as shown in Fig. 6.2.

Worked solution & mark scheme

This 11-mark question has a full step-by-step worked solution and mark scheme. One marking point: Magnetic flux is the product of flux density and area

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