Справочник Пользователя для PASCO Specialty & Mfg. AC/DC Electronics Laboratory EM-8656

109

012-05892A

AC/DC Electronics Laboratory

®

– Computer and Science Workshop™  Interface
– Voltage Sensor (CI-6503)
– AC/DC Electronics Lab Board (EM-8656)
– Alnico bar magnet (EM-8620)
– OPTIONAL: Photogate (ME-9204A or ME-9498)

This experiment shows the Electromotive Force (EMF) induced in a coil by a magnet dropping
through the center of a coil.

When a magnet is passed through a coil there is a changing magnetic flux through the coil which
induces an Electromotive Force (EMF) in the coil. According to Faraday’s Law of Induction:

ε

= −

∆

φ

∆

where 

ε

 is the induced EMF, N is the number of turns of wire in the coil, and 

∆ φ 

∆ 

t 

 is the rate of

change of the flux through the coil.

In this experiment, a plot of the EMF vs. time is made and the area under the curve is found by
integration. This area represents the flux since

ε

∆

= −

∆

φ

➀

Connect the Science Workshop interface to the computer, turn on the interface, and turn on the
computer.

➁

Plug the DIN plug of the Voltage Sensor into Analog Channel A.