Page 689 - SUBSEC October 2017_Neat

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Item 11 refers to the following diagram. 14. Which diagram correctly shows the
direction of the forces acting on adjacent
current carrying conductors?

2A (A)

11. A hollow solenoid has 100 turns in a length (B)
of 0.5 m. If a steady current of 2A flows
in the solenoid as shown in the diagram, (C)
what is the magnitude and direction of the
flux density in the middle? (D)

(A) 1.3 x 10 T to the left
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(B) 5.0 x 10 T to the left 15. The following diagrams illustrate a
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(C) 1.3 x 10 T to the right demonstration of Lenz’s law of
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(D) 5.0 x 10 T to the right electromagnetic induction. In which
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diagram is the current in the correct
direction?
12. A wire of length 0.5 m and resistance 5Ω
moves vertically with a velocity of 10 m s
-1
perpendicular to a uniform magnetic field (A) S N
of flux density 4.0 x 10 T. What is the
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magnitude of the e.m.f. generated between
the ends of the wire?

(A) 1.0 x 10 V
-4
(B) 2.0 x 10 V
-4
(C) 4.0 x 10 -4 V (B) S N
(D) 8.0 x 10 V
-4

13. An electron beam moving with speed v
enters a uniform magnetic field B, acting
down the page as shown. (C) N S

X

r

electron beam B (D) N S

Y
The beam of electrons will bend

(A) out of the paper
(B) into the paper
(C) towards X
(D) towards Y

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02238010/SPEC 2017