Lucas plugs a lamp into the wall. the light bulb in the lamp turns on. what kind of energy transformation is this?
a.
light energy is transformed into electrical and mechanical energy.
b.
electrical energy is transformed into light and heat energy.
c.
light energy is transformed into mechanical and heat energy.
d.
electrical energy is transformed into mechanical and heat energy.

In the circuit, the switch s has been open for a long time and r = 125 kohm. it is then suddenly closed. (a) determine the time constant before the switch is closed. s (b) determine the time constant after the switch is closed. _ s (c) let the switch be closed at t = 0. find the current in the switch as a function of time. (use t for time. express your answer in milliamps and seconds.) i(t) =_