Select Pick up coil.

If a conducting wire is placed in a changing magnetic field, the magnetic field induces an electric potential on the electrons. The potential is called electromotive force emf (measured in Volts), which the electrons can lose on an external resistor (or any electric device) that converts their electric energy into other forms of energy.

Determine, using the simulation, how the following parameters affect the magnitude of the induced electromotive force, (epsilon). Use the following general math symbolism as it applies: ~ 1 / or ~. a) As the sectional area(A) increases; _______________________ ~_____________

b) As the Intensity of the external magnetic field B increases, _______________________ ~_____________

c) As the number of loops (coils), N, of the circuit with the light bulb increase; _____________________ ~_____________

d) There is also a factor in how the magnetic field lines enter the loop area (at what angle). This factor cannot be explored using the simulation (see p.956 of the book instead). You would expect that if the magnet enters to loop positioned horizontally, the effect on the electromotive force will be the highest. Thus, using algebra, when the vector of the area (vector area is perpendicular to the surface area) and the vector of B are parallel, the angle between them is 0^degree, and it decreases to zero when the angle is 90o . The effect of (a) and (b) is called a magnetic flux: sigma = .

Max Flux = 0 degree, Zero Flux = 90degree and Flux=B cos theta

e) Combining a-d, one can claim that: ~sigma ~ ___________(1)

There is a negative sign in front of the right side due to the convention for induced emf. This is because the number of loops N is excluded from the flux calculations in some textbooks.

Equation (1) is a proportionality statement that needs a constant to formulate an equation.

f) Try to move to the magnet with a higher and lower rate of change / and observe the effect on the induced emf. As / increases _______________

Combine all parameters and formulate a formula to calculate . Verify with the textbook (p. =

________________

It was proven that emf could be induced when B changes or when the area or the angle changes; thus, the derivative is traditionally included in front of the entire expression and applied respectively using differentiation rules. = sigma/dt = d /

: = /

: = /

: = /

If two parameters change simultaneously, a product rule for differentiation must be applied. However, in problem-solving, the rates are usually provided numerically.