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Chapter 20: Q60P (page 861)

A neutral iron bar is dragged to the left at speed v through a region with a magnetic field B points out of the page (Figure 20.122). Which diagram (1-5) best shows the state of the bar?

Short Answer

Expert verified

The correct diagram is (3).

Step by step solution

01

Given Data

speed=vmagnetic field=B

02

Concept

The speed is perpendicular to the magnetic field.

03

Step 3(a): Find which diagram shows the state of the bar

When the bar moves through a uniform magnetic field, the particles with charge q > 0 inside the bar experience a magnetic force

F→=qv→×B→

Here B→ is out of plane and v→ is directed towards the left.

F→ is directed upward.

This tends to push the +ve charges upward leaving –ve charges on the lower end.

Hence the correct diagram is (3).

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Most popular questions from this chapter

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