Activities/Turtle Art/Using Turtle Art Sensors: Difference between revisions
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Unlike the current transformer (previously) which can only sense AC amps, the Hall Effect sensor can also sense DC amps. It does this by measuring the magnetic field that a current creates. | Unlike the current transformer (previously) which can only sense AC amps, the Hall Effect sensor can also sense DC amps. It does this by measuring the magnetic field that a current creates. | ||
[[File:Amperes law.png]] | [[File:Amperes law.png]] http://en.wikipedia.org/wiki/Amp%C3%A8re%27s_circuital_law | ||
*μ0 = | *μ0 = 4π×10^−7 N·A−2 | ||
*B in tesla (1 gauss = 10^-4 tesla) | *B in tesla (1 gauss = 10^-4 tesla) | ||
*l in metres | *l in metres | ||
*i in amps | *i in amps | ||
and in the case of the magnetic field B at a radius r from a wire, the left side integral evaluates to B2πr | and in the special case of the magnetic field B at a radius r from a wire in free space, the left side integral evaluates to B2πr and at a radius if 1cm from a wire carrying 1 amp , the field is 4π10^-7/2π10^-2 = 2x10^-5 tesla or 2x10^-1 gauss | ||
==Links== | ==Links== | ||