# Homework Help: Can the magnetive field of a pedometer be cancelled at a very small scale

1. Jun 16, 2011

### syahrul123

1. The problem statement, all variables and given/known data
Okay , i am trying to know if a compass will work alongside a pedometer , under a very weak battery. What i mean by this is that will there be a large scale interference if the compass is placed next to it. I am trying to do such since, according to my schoolwork have to produce a new idea for navigation offline . I know the presence of the magnetic waves from the battery powering the pedometer , but will this be large enough to displace the accuracy of the compass rendering it unusable? The battery that i am using is a 3v battery. The battery , compass and pedometer will all be placed in a single case. The case will then be used as an extension for the iphone , where the iphone will tabulate data from the pedometer and compass

2. Relevant equations

3. The attempt at a solution

At first i did research on gyroscopes. At the current rate that i am going , i do not think that creating a gyroscope at such a small level is possible

Second, i also searched on flux gate technology. However i did not understand much of this seeing that i am only taking my A-levels this year and have not even started on my electrical topics yet.

Third, i am rather interested if it is possible to produce a faraday's cage . I already understand the concepts of the faraday cage , such that it blocks out external electrostatic forces but not the earth's ones , thus by enclosing the compass in the cage, the compass will work normally since the cage. However my main question is this : is this possible at the micro-level saying a spherical faraday cage of 5cm.From my research , the faraday cage requres a current to flow through it no? In my situation the same battery that powers the pedometer will power the cage.

Thank you , i hope that you can understand my description :D

2. Jun 16, 2011

### RTW69

Do an experiment. Get a small compass and slowly move your pedometer close to it. Did the compass needle move? If so was it caused by magnetic effects of the pedometer or was there some metal in the pedometer? A little experimentation should give you an answer.